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                                                                     EXHIBIT 4.5

                            FOURTH AMENDMENT TO FIFTH
                       AMENDED AND RESTATED LOAN AGREEMENT

     This Fourth Amendment (the "Amendment") dated as of October 29, 1999, is
between Bank of America, N.A. (formerly known as Bank of America National Trust
and Savings Association) (the "Bank") and Ducommun Incorporated, a Delaware
corporation (the "Borrower"),

                                    RECITALS

     A. The Bank and the Borrower entered into a certain Fifth Amended and
Restated Loan Agreement dated as of June 23, 1997, as amended by a First
Amendment dated as of October 1, 1997, a Second Amendment dated as of August 10,
1998, and a Third Amendment dated as of February 11, 1999, (as amended, the
"Agreement").

     B. The Bank and the Borrower desire to further amend the Agreement.

                                    AGREEMENT

     1.   Definitions. Capitalized terms used but not defined in this Amendment
shall have the meaning given to them in the Agreement.

     2.   Amendments. The Agreement is hereby amended as follows:

          2.1 In Paragraph 1.1 of the Agreement, the definition of "Permitted
Acquisition" is amended to add to the end of subparagraph (vii) thereof,
immediately following the word "Acquisition," the following:

               ", excluding from the calculation made under this subparagraph,
               any Acquisition that (A) occurred prior to September 30, 1999 or
               (B) is financed exclusively from balance sheet cash derived from
               sources other than Loans under this Agreement and, after giving
               effect to such Acquisition, no Loans are outstanding under this
               Agreement."

          2.2 In Paragraph 1.1 of the Agreement, the definition of "Termination
Date" is amended to read:

               "`Termination Date' means July 1, 2002."

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          2.3 The last phrase of subparagraph (c) of Paragraph 6.3 of the
Agreement, commencing with the words "provided further, however," is amended in
full to read as follows:

               "; provided, further, however, that the amount of the following
               transactions shall not be included in calculating the amount of
               redemptions or repurchases of shares permitted under clause (c)
               of this Paragraph 6.3: common stock repurchases that (i) occurred
               prior to September 30, 1999, or (ii) are financed exclusively
               from balance sheet cash derived from sources other than Loans
               under this Agreement and, after giving effect to such redemptions
               or repurchases, no Loans are outstanding under this Agreement."

     3. Representations and Warranties. When the Borrower signs this Amendment,
the Borrower represents and warrants to the Bank that: (a) there is no event
which is, or with notice or lapse of time or both would be, a default under the
Agreement, (b) the representations and warranties in the Agreement are true as
of the date of this Amendment as if made on the date of this Amendment, (c) this
Amendment is within the Borrower's powers, has been duly authorized, and does
not conflict with any of the Borrower's organizational papers, and (d) this
Amendment does not conflict with any law, agreement, or obligation by which the
Borrower is bound.

     4.   Conditions Precedent. This Amendment will be effective when the Bank
receives the following items, in form and content acceptable to the Bank:

          4.1  An amendment fee in the amount of $12,000.

          4.2  Evidence that the execution, delivery and performance of this
     Amendment by the Borrower has been duly authorized.

     5.   Conditions Subsequent. The Borrower agrees to deliver to Bank, within
five (5) days of the effective date of this Amendment, an Instrument of Joinder,
duly executed by Parsons Precision Products, Inc., together with corporate
resolutions authorizing such guaranty by joinder, certified by their respective
Secretary or Assistant Secretary. The Borrower acknowledges that the failure to
deliver these documents to the Bank within the time provided herein shall
constitute a default under the Agreement.

     6. Effect of Amendment. Except as provided in this Amendment, all of the
terms and conditions of the Agreement shall remain in full force and effect.

                            (Signature page follows)

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     This Amendment is executed as of the date stated at the beginning of this
Amendment.

                                        Bank of America, N.A.

                                        By: /s/ J. Thomas Fagan
                                            ------------------------------------
                                            J. Thomas Fagan
                                            Vice President

                                        Ducommun Incorporated

                                        By: /s/ K. R. Pearson
                                            ------------------------------------
                                            Kenneth R. Pearson
                                            Vice President--Human Resources
                                            And Assistant Secretary

                                        By: /s/ James S. Heiser
                                            ------------------------------------
                                            James S. Heiser
                                            Vice President, Treasurer,
                                            Secretary, and
                                            Chief Financial Officer

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                                                                    EXHIBIT 10.5

                              DUCOMMUN INCORPORATED

                             STOCK OPTION AGREEMENT

This stock option agreement is made as of [date] (the "Effective Date"), between
DUCOMMUN INCORPORATED, a Delaware corporation (the "Corporation"), and [name]
("Option Holder").

                                 R E C I T A L S

This stock option agreement is pursuant to the [plan name] (the "Plan"). This
stock option agreement DOES NOT represent an incentive stock option as defined
in Section 422A of the Internal Revenue Code. This stock option agreement
expires on [date] (the "Expiration Date").

                               A G R E E M E N T S

     1. Grant. The Corporation hereby grants to the Option Holder the right and
option to purchase, on the terms and conditions hereinafter set forth, all or
any part of an aggregate of [#] shares of the Common Stock at the purchase price
of $[price] per share, being 100% of the fair market value of the Common Stock
on the date the option is granted, exercisable from time to time in accordance
with the provisions of this Agreement until the close of business on the
Expiration Date.

     2. Definitions. Unless the context clearly indicates otherwise, and subject
to the terms and conditions of the Plan as the same may be amended from time to
time, the following terms, when used in this stock option agreement, shall have
the meanings set forth in this Section 2.

          "Common Stock" shall mean the Common Stock, $.01 par value, of the
     Corporation or such other class of shares or other securities as may be
     applicable pursuant to the provisions of Section 7 of this stock option
     agreement.

          "Subsidiary" shall mean a corporation or other form of business entity
     more than 50% of the voting shares of which is owned or controlled,
     directly or indirectly, by the Corporation and which is designated by the
     Committee for participation in the Plan by the key employees thereof.

          "Committee" shall mean the Compensation Committee of the Board of
     Directors of the Corporation, or if there is no such committee acting, the
     Board of Directors of the Corporation.

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     3. Conditions to Exercise. The Option Holder may not purchase any shares by
exercise of this option unless the Option Holder shall have remained in the
employ of the Corporation and/or a Subsidiary until at least [date]. On and
after [date], the Option Holder may purchase, by exercise of this option, an
aggregate of not more than one-fourth of the total number of shares subject to
this option. On and after [date], the Option Holder may purchase, by exercise of
this option, an additional one-fourth of such total number of shares. On and
after [date], the Option Holder may purchase, by exercise of this option, an
additional one-fourth of such total number of shares. On and after [date], until
this option expires, the Option Holder may purchase, by exercise of this option,
all or any part of the shares subject to this option. Provided, however, that
until this option expires, the Option Holder may purchase, by exercise of this
option, all or any part of the shares subject to this option at any time after a
"Change in Control" of the Corporation has occurred. For purposes of this stock
option agreement, a "Change in Control" of the Corporation shall mean a change
in control of a nature that would be required to be reported in response to Item
6(e) of Schedule 14A of Regulation 14A promulgated under the Securities Exchange
Act of 1934, as amended (the "Exchange Act"); provided that, without limitation,
such a change in control shall be deemed conclusively to have occurred if (i) a
tender offer shall be made and consummated for the ownership of 25% or more of
the outstanding voting securities of the Corporation, (ii) the shareholders of
the corporation approve that the Corporation be merged or consolidated with
another corporation and as a result of such merger or consolidation less than
75% of the outstanding voting securities of the surviving or resulting
corporation shall be owned in the aggregate by the former shareholders of the
Corporation, other than affiliates (within the meaning of the Exchange Act) of
any party to such merger or consolidation, as the same shall have existed
immediately prior to such merger or consolidation, (iii) the shareholders of the
Corporation approve that the Corporation sell, lease, exchange or transfer
substantially all of its assets to another corporation, entity or person which
is not a wholly-owned subsidiary, (iv) a person, as defined in Sections 13(d)
and 14(d) (as in effect on the date hereof) of the Exchange Act, shall acquire
25% (or in the case of The Clark Estates, Inc., 30%) or more of the outstanding
voting securities of the Corporation (whether directly, indirectly, beneficially
or of record), (v) the shareholders of the Corporation approve a plan or
proposal for the liquidation or dissolution of the Corporation, or (vi) during
any period of two consecutive years, individuals who at the beginning of such
period constitute the Board of Directors cease for any reason to constitute at
least a majority thereof unless the election, or the nomination for election by
the Corporation's shareholders, of each new director was approved by a vote of
at least two-thirds of the directors then still in office who were directors at
the beginning of the period. For purposes hereof, ownership of voting securities
shall take into account and shall include ownership as determined by applying
the provisions of Rule 13d-3 (as in effect on the date hereof) under the
Exchange Act. A sale or other change in control of any Subsidiary of the
Corporation by which the Option Holder is employed shall not be deemed a Change
in Control of the Corporation for purposes of this Agreement.

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     4. Exercise by the Option Holder. This option may be exercised solely by
the Option Holder, except as provided in Section 5 below in the event of the
Option Holder's death.

     5. Termination. This option shall terminate if and when the Option Holder
shall cease to be an employee of the Corporation or a Subsidiary, except as
follows:

          (a) Death. If the Option Holder dies while employed by the Corporation
     or a Subsidiary, or while this option was exercisable by him in accordance
     with paragraph (b) or (c) below after his retirement, permanent disability
     or the termination of his employment other than for cause, this option may
     be exercised (for not more than the number of shares as to which the Option
     Holder might have exercised this Option at the time of such death) by the
     personal representative of the decedent or, by such person or persons as
     shall have acquired the Option Holder's rights under this option by will or
     by the laws of descent and distribution at any time (i) prior to the
     Expiration Date, in the event the Expiration Date is not more than one year
     following the date of death, or (ii) within such one year, in the event
     that the Expiration Date is more than one year following such date of
     death;

          (b) Retirement or Permanent Disability. If the Option Holder retires
     or becomes permanently disabled, this option may be exercised (for not more
     than the number of shares as to which the Option Holder might have
     exercised this option on the date of his retirement or permanent
     disability) at any time prior to the Expiration Date. As used herein,
     "retirement" shall mean the date on which the Option Holder voluntarily
     terminates his employment with the Corporation or a Subsidiary with the
     permanent intention of not seeking other employment or becoming
     self-employed except for part-time consulting; and "permanent disability"
     shall mean the date on which the Option Holder has not worked or been able
     to work due to physical or mental incapacity for a period of 180
     consecutive days.

          (c) Other Termination. If the employment of the Option Holder with the
     Corporation or a Subsidiary is terminated for any reason other than by
     death, permanent disability or retirement, this option may be exercised
     (for not more than the number of shares as to which the Option Holder might
     have exercised this option on the date on which his employment was
     terminated) at any time (i) prior to the Expiration Date in the event the
     Expiration Date is not more than three months following the date of such
     retirement or termination, or (ii) within such three-month period, in the
     event that the Expiration Date is more than three months following the date
     of such termination of employment; provided, however, that if the Option
     Holder is dismissed for cause, of which the Committee shall be the sole
     judge, this option shall terminate forthwith.

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The Committee may determine that, for the purpose of the Plan, the Option Holder
while on a leave of absence will be considered as still in the employ of the
Corporation, provided that this option shall be exercisable during a leave of
absence only as to the number of shares as to which it was exercisable at the
commencement of such leave of absence.

     6. Method of Exercise. A person electing to exercise this option shall
deliver to the Secretary of the Corporation a written notice of such election
and of the number of shares such person has elected to purchase and shall at the
time of exercise tender the full purchase price of the shares such person has
elected to purchase.

     7.   Adjustments

          (a) If the outstanding shares of Common Stock of the Company are
increased, decreased, changed into or exchanged for a different number or kind
of shares or securities of the Company through recapitalization (other than the
conversion of convertible securities according to their terms),
reclassification, stock dividend, stock split or reverse stock split, an
appropriate and proportionate adjustment shall be made, or if the Company shall
spin-off, spin-out or otherwise distribute assets with respect to the
out-standing shares of Common Stock of the Company, an appropriate and
proportionate adjustment may be made in the discretion of the Committee, in (i)
the maximum number and kind of shares as to which options may be granted under
the Plan, (ii) the number and kind of shares subject to outstanding options, and
(iii) the exercise price for each share under outstanding options, without any
change in the aggregate purchase price or value applicable to the unexercised
portion of the outstanding options.

          (b) In the event of the dissolution or liquidation of the Company, or
upon any merger, consolidation or reorganization of the Company with any other
corporations or entities as a result of which the Company is not the surviving
corporation, or upon the sale of all or substantially all of the assets of the
Company or the acquisition of more than 80% of the stock of the Company by
another corporation or entity, there shall be substituted for each of the shares
of Common Stock then subject to the Plan the number and kind of shares of stock,
securities or other assets which would have been issuable or payable in respect
of or in exchange for such Common Stock then subject to the Plan, as if the
optionee had been the owner of such shares as of the transaction date. Any
securities so substituted shall be subject to similar successive adjustments.

     8. No Right to Continued Employment. Nothing in the Plan, in this stock
option agreement or in any other instrument executed pursuant thereto shall
confer upon the Option Holder any right to continue in the employ of the
Corporation or any Subsidiary of the Corporation or shall interfere in any way
with the right of the Corporation or any such Subsidiary to at any time
terminate the employment of the Option Holder with or without cause.

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     9. Legal Requirements. No shares issuable upon the exercise of this option
shall be issued or delivered unless and until, in the opinion of counsel for the
Corporation, all applicable requirements of federal and state law and of the
Securities and Exchange Commission pertaining to the issuance and sale of such
shares and any applicable listing requirements of any national securities
exchange on which shares of the same class are then listed, shall have been
fully complied with. In connection with any such issuance or transfer, the
person acquiring the shares shall, if requested by the Corporation, give
assurances satisfactory to counsel to the Corporation in respect of such matters
as the Corporation or any Subsidiary of the Corporation may deem desirable to
assure compliance with all applicable legal requirements.

     10. No Rights as a Shareholder. Neither the Option Holder nor any
beneficiary or other person claiming under or through the Option Holder shall
have any right, title or interest in or to any shares of Common Stock allocated
or reserved for the purpose of the Plan or subject to this Agreement except as
to such shares of Common Stock, if any, as shall have been issued or transferred
to such person.

     11. Withholding. The Corporation or any Subsidiary of the Corporation may
make such provisions as it may deem appropriate for the withholding of any taxes
which the Corporation or such Subsidiary determines it is required to withhold
in connection with this stock option agreement and the transactions contemplated
hereby, and the Corporation or any such Subsidiary may require the Option Holder
or other person exercising this Option to pay to the Corporation or such
Subsidiary in cash any amount or amounts which may be required to be paid as
withheld taxes in connection with any exercise of this Option or any other
transaction contemplated hereby as a condition to the exercise of this Option
and issuance of shares of the Common Stock.

     12. No Assignments. Neither this stock option agreement, not this option
nor any other rights and privileges granted hereby shall be transferred,
assigned, pledged or hypothecated in any way, whether by operation of law of
descent and distribution. Upon any attempt to so transfer, assign, pledge,
hypothecate or otherwise dispose of this stock option agreement, this option or
any other right or privilege granted hereby contrary to the provisions hereof,
this stock option agreement, this option and all of such rights and privileges
shall immediately become null and void.

     13. Other Programs. Nothing contained in this stock option agreement shall
affect the right of the Option Holder to participate in and receive benefits
under and in accordance with the then current provisions of any pension,
insurance, profit-sharing or other employee benefit plan or program of the
Corporation or of any Subsidiary of the Corporation.

     14. The Plan. The option hereby granted is subject to, and the Corporation
and Option Holder agree to be bound by all of the terms and conditions of the
Plan as the same may be amended from time to time in accordance with the terms
thereof, but

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no such amendment may adversely affect the Option Holder's rights
under this stock option agreement. Option Holder acknowledges receipt of a
complete copy of the Plan.

     15. Consideration. The consideration for the rights and benefits conferred
on Option Holder by this option are the services rendered by the Option Holder
after and not before the grant of this option.

     16. Applicable Law. This option has been granted as of the effective date
set forth above at Los Angeles, California, and the interpretation, performance
and enforcement of this Agreement shall be governed by the laws of the State of
California.

DUCOMMUN INCORPORATED

By:
    ------------------------------------
                       President and CEO

By:
    ------------------------------------
                               Secretary

                                            ------------------------------------
                                                                   Option Holder

By his or her signature, the spouse of the Option Holder hereby agrees to be
bound by all the terms and conditions of this written stock option agreement.

                                           -------------------------------------
                                                         Spouse of Option Holder

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