Someone PM'ed me and reminded me that I never posted any completed photos of the ammeter in the car.

If I had it to do over, I would at least investigate if there is some way to print clear overlay decals at home, and I'd copy the face of the voltmeter onto a decal and apply that to the old ammeter face. Or, it is possible that a company that does vehicle wraps could make such a decal, using the original voltmeter face as a template. It would look better that way, but I'm probably not going to tear it apart at this point and re-do it.