Some of us use a heat gun and there are release agents that help.
I've used dual stripe strips on my BMW for that classic look.
Have you considered flame decals for effect?
After repainting my Wee I got custom made Horned Toad decals to replace the big S.
The S is just glued on. I removed mine last week with the help of a heat gun and dental floss. The logo came off pretty easy and I didn't need any chemicals to get the rest of the glue residue off, just worked it off while still warm with my fingers.
I then found a place online that prints custom vinyl stickers and takes small orders (stickylife.com) - got 4 3" diameter circle custom stickers for about $20 total.