'68 'Cuda fuel cap/door removal

The body shop told me they are unable to remove the fuel flip cap on my 68 Barracuda. They want to take a grinding wheel to the three bolt heads on the shiney side, but they think they may damage it. Is this a common problem? Are they over looking something? I haven't looked if a new fuel door is available yet, but thought I check here first. They're in the process of replacing the quarter skins.

Thanks!
Eric