by "exterior trim" are you talking about the pinstripe, or part of the body cladding?
if it is the pinstripe, they can be removed pretty easily. I found something like this at my local auto parts store http://www.eastwoodco.com/shopping/p...ripe%2Cremoval
it works better then any other method I tried, much much faster and worth the money. my car is red, and my parts car is red also, but had some gold pinstriping on it. after I removed the stripes, there is still a little bit of a line there, but usually a good polish or maybe even a clay bar would remove the lines.
that eraser is the way to go for pinstripe removal, I tried the hair dryer trick..... very very long time for little progress. with the eraser on my drill, I did both front fenders and the back passenger door in about 30 - 45 minutes, if that
hope this helps