Paint Stripping on Raider Handle?

So I recently received a used Rampage from a friend, and I wanted to give it a little weathering and a strong clear coat (keeping the original paint scheme), but I've run into some issues.

I recently purchased Rustoleum American Accents clear coats in Matte and Gloss, as I was told some users have found success in them, and I don't have the cash for 2K. I tried testing it on my Raider, just to get comfortable with using it, and it stripped the gray paint off the handle and nameplate on the Raider. The only thing that didn't seem to strip the paint was a Polyurethane coat, but that chipped immediately. Currently considering putting a Poly coat over the handle and a Gloss coat over the whole thing.

Has anyone else had this issue? Will it also happen on the Rampage? Any other fixes?