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                                                                  EXHIBIT 10.103

                                                                  EXECUTION COPY

                    SUPPLEMENT TO BACKUP SERVICING AGREEMENT

         This Supplement, dated as of March 31, 1999, by and among National
Financial Auto Funding Trust ("Funding Trust"), National Auto Finance Company,
Inc. ("NAFI", formerly National Auto Finance Company LP) and Harris Trust and
Savings Bank ("Harris") (the "Supplement") to the Backup Servicing Agreement,
dated as of March 31, 1998, by and among Funding Trust, NAFI and Harris (the
"Agreement").

                               W I T N E S E T H:

         WHEREAS, Funding Trust, NAFI and Harris wish to supplement the
Agreement in accordance with the terms of this Supplement;

         NOW THEREFORE, the parties hereby agree, in consideration of the mutual
promises and mutual obligations set forth herein, to the terms and conditions of
the Agreement as amended by this Supplement.

         SECTION 1 Survival of the Agreement. Nothing contained herein or
contained in the Agreement for Monitoring and Backup Servicing, dated as of the
date hereof (the "LSE Agreement"), by and among NAFI, CSC Logic/MSA LLP d/b/a
Loan Servicing Enterprise and Financial Security Assurance Inc. ("FSA"), shall
terminate the Agreement. Except as explicitly provided herein, the terms of the
Agreement shall continue to govern, and the rights and responsibilities of the
parties under the Agreement shall survive the parties' entry into this
Supplement and NAFI's entry into the LSE Agreement.

         SECTION 2 Suspension of Obligations.

         (a) Harris' duty to perform its duties as Backup Servicer under the
Agreement and Harris' entitlement to collect payments for services under the
Agreement, in each case arising after the date hereof, are hereby suspended from
the date of the signing of this Supplement until such date, if any, as the
parties to this Supplement are given written notice by FSA that the LSE
Agreement has been terminated and that they are to resume performance under the
Agreement (the "Notice Date"). NAFI's duty to pay Harris for its performance of
its duties as Backup Servicer incurred after the date hereof under the Agreement
is hereby suspended from the date of the signing of this Supplement until the
Notice Date. Harris and NAFI hereby agree that as of the date hereof no amounts
are due and outstanding to Harris under the Agreement and no performance of
duties under the Agreement are due and outstanding by Harris or NAFI. After the
Notice Date, the provisions of this Supplement will terminate and the parties
will resume their respective duties and obligations under the Agreement.

         (b) FSA hereby agrees for the benefit of Harris as Backup Servicer
pursuant to the Pooling and Servicing Agreement, dated as of October 1, 1995,
and the Pooling and Servicing Agreement, dated as of October 21, 1996, each
among Funding Trust, NAFI, and Harris, as Trustee, and for the benefit of Harris
as Standby Servicer pursuant to the Sale and Servicing Agreement, dated as of
June 29, 1997, among Funding Trust, NAFI, Harris and the National Auto Finance
1997-1 Trust, and the Sale and Servicing Agreement, dated as of December 15,




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1997, among Funding Trust, NAFI, Harris, as Trust Collateral Agent and Backup
Servicer, and the National Auto Finance 1998-1 Trust (such agreements, the
"Underlying Agreements"), that so long as the Notice Date has not occurred, FSA
will not appoint Harris as successor servicer under the Underlying Agreements.

         SECTION 3 Limited Effect. Except as expressly set forth in this
Supplement, the Agreement shall continue to be, and shall remain, in full force
and effect in accordance with its terms.

         SECTION 4 Counterparts. This Supplement may be executed by each of the
parties hereto on any number of separate counterparts, each of which shall be an
original and all of which taken together shall constitute one and the same
instrument.


         SECTION 5. GOVERNING LAW. THIS SUPPLEMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK WITHOUT REFERENCE
TO THE CHOICE OF LAW PROVISIONS THEREOF.



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         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Agreement to be duly executed and delivered as of the date first above
written.

                                       HARRIS TRUST AND
                                       SAVINGS BANK

                                       By:    /s/ E. KAY LIEDERMAN
                                          --------------------------------------
                                       Name:  E. Kay Liederman
                                       Title: Vice President


                                       NATIONAL FINANCIAL AUTO
                                       FUNDING TRUST

                                       By:  CHASE MANHATTAN
                                            BANK DELAWARE, not in its
                                            individual capacity but solely as
                                            Owner Trustee

                                       By:  /s/ DENIS KELLY
                                          --------------------------------------
                                       Name:  Denis Kelly
                                       Title: Trust Officer


                                       NATIONAL AUTO FINANCE
                                       COMPANY INC.

                                       By:    /s/ STEPHEN R. VETH
                                          --------------------------------------
                                       Name:  Stephen R. Veth
                                       Title: Vice President, Secretary and
                                              General Counsel



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ACKNOWLEDGED AND ACCEPTED:

FINANCIAL SECURITY ASSURANCE INC.

By:    /s/ RICHARD J. BAUERFELD
    --------------------------------------
Name:   Richard J. Bauerfeld
Title:          MD


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