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Thanks TD. So Boeing’s objection to the wiring change on the grounds of chafing while removing is an invalid one.
What the FAA wants isn't to remove an individual wire but to remove and reconfigure multiple wire bundles; apparently by re-looming the wires into entirely new bundles.
It's tough enough to correctly fabricate and maintain bundles before installation with all the room of a factory floor - my experience is military ground vehicles up to 50 feet in length. Essentially remanufacturing the wiring post install in the confines of a fuselage is asking for nearly innumerable defects.
Running a wire all by itself alongside an existing bundle is a bad idea as it will easily move and chafe and fatigue or wear through, allowing short circuits or corrosion.