Last year I applied some of that aluminum tape (not duct tape) over top of the galvanized area in the tail lights on my 68 Ford.
The left tail light is the light with the tape before doing the right side to see if it made any difference.
I think it helped. There is this debate I've read on other car forums on whether using silver tape versus white paint is better. Some people think white paint is more reflective. I don't see how it could be.
Anyway, I'm planning on doing this to all my cars. The problem with my Spider is it doesn't look as if the lens portion of tail light can be removed from the back housing. I'm going to have to dig for a set of spare tail lights in my barn loft because I'm not pulling the whole tail light out then be disappointed the tail light is molded into one piece.
Has anyone had any luck doing what I am wanting to do? Can these tail lights be separated?