Stubborn decals on alloy rims

I have a pair of SRAM Roam 50 wheels (like this) with very excessive decals. I’m trying to remove them but no known method seems to work. The following methods have failed (= don’t even scratch the surface):

• Heat Gun
• Plastic Razor
• Isopropyl alcohol
• WD40
• Any combination of the above

The only method that has (very little) success is an old school razor (metal) – but that scratches the rim.

Is it possible that there’s a clear coat on top of these stickers?

Has anyone encountered such stubborn rim decals and won the war?