Acrylic will soften up with gas every time. I've never used polyurethane, I know others here have and it will hold up to gas. I've used 2 part urethane (paint and clear together) and it's 100% fuel proof. I don't know the difference in the poly, but I'm sure a quick google search would explain. There is an auto paint supply house here that can custom mix any 2 part urethane color into a rattle can. Clear coat also. There is a plug on the bottom of the can you pull to release the catalyst. Shake like hell and you have approx. 12 hours to use it. (depending on temp) It works great on saws. I hate cleaning my paint gun. I think, as long as the TSC paint is 100% cured, the urethane clear coat shouldn't lift it. If I remember correctly, I sprayed some over some Valspar tractor paint before and it was fine. The Valspar was enamal, which is what the TSC implement paint most likely is.