A panel mount connector, comprising: a connector shell assembly (20, 250) configured to be received in an opening that is defined by a panel, the connector shell assembly (20, 250) defining a through passage; and a flexible circuit board supported substantially within the through passage and defining a first external connection interface at one end thereof for external electrical access from one side of the panel when the connector shell assembly (20, 250) is installed therein; and defining a second external connection interface at an opposing end of the flexible circuit board for external access from an opposite side of the panel when the connector shell assembly (20, 250) is installed therein; with: the second external connection interface including at least one of an electrical connection interface for external electrical communication on the opposing side of the panel and an optical connection interface for external optical communication on the opposing side of the panel; the connector shell assembly (20, 250) including: a main connector shell body that defines a first entrance opening from which the first external connection interface is accessed when the flexible circuit board is received in the through passage; the panel mount connector being characterized in that the connector shell assembly (20, 250) further includes a retainer ring configured for removably fixed engagement with the main connector shell body at the first entrance opening, the retainer ring being further configured for capturing the first external connection interface for independent movement of the first external interface relative to the connector shell assembly (20, 250). a connector shell assembly (20, 250) configured to be received in an opening that is defined by a panel, the connector shell assembly (20, 250) defining a through passage; and a flexible circuit board supported substantially within the through passage and defining a first external connection interface at one end thereof for external electrical access from one side of the panel when the connector shell assembly (20, 250) is installed therein; and defining a second external connection interface at an opposing end of the flexible circuit board for external access from an opposite side of the panel when the connector shell assembly (20, 250) is installed therein; with: the second external connection interface including at least one of an electrical connection interface for external electrical communication on the opposing side of the panel and an optical connection interface for external optical communication on the opposing side of the panel; the connector shell assembly (20, 250) including: a main connector shell body that defines a first entrance opening from which the first external connection interface is accessed when the flexible circuit board is received in the through passage; the panel mount connector being characterized in that the connector shell assembly (20, 250) further includes a retainer ring configured for removably fixed engagement with the main connector shell body at the first entrance opening, the retainer ring being further configured for capturing the first external connection interface for independent movement of the first external interface relative to the connector shell assembly (20, 250). the second external connection interface including at least one of an electrical connection interface for external electrical communication on the opposing side of the panel and an optical connection interface for external optical communication on the opposing side of the panel; the connector shell assembly (20, 250) including: a main connector shell body that defines a first entrance opening from which the first external connection interface is accessed when the flexible circuit board is received in the through passage; the panel mount connector being characterized in that the connector shell assembly (20, 250) further includes a retainer ring configured for removably fixed engagement with the main connector shell body at the first entrance opening, the retainer ring being further configured for capturing the first external connection interface for independent movement of the first external interface relative to the connector shell assembly (20, 250). a main connector shell body that defines a first entrance opening from which the first external connection interface is accessed when the flexible circuit board is received in the through passage; the panel mount connector being characterized in that the connector shell assembly (20, 250) further includes a retainer ring configured for removably fixed engagement with the main connector shell body at the first entrance opening, the retainer ring being further configured for capturing the first external connection interface for independent movement of the first external interface relative to the connector shell assembly (20, 250).