Mike, I appreciate your input. Your earlier comment about "de-militarizing" the car may prove to be the best path forward. I will most likely remove most of the emergency lights to keep from drawing attention to the car on the road, and prevent any hassles with the Federales. I think it would be better to keep the car clutter-free in terms of police equipment, rather than need to put signs on the car that say it is NOT IN SERVICE.
Presently, all markings have been removed except the rocker stripe (which is now fully masked). I like your comment about having the lettered magnets be for display-only, and leaving the car unmarked. The 8" LeMans stripes are cracked and faded so badly that the silver almost looks white. I plan to re-do those stripes, and could easily do the rockers at the same time with
a plain stripe in the same color as the new ones going over the car. Then I could have a magnet done for display purposes to replicate the TRAFFIC ENFORCEMENT lettering. That's a really good suggestion, the more I think about it.