how to shave the gas cap on my demon

I guess you have a cap that is flush but the handle part protrudes out past the body? A picture would go a long way.....You can grind that off but then you will not be able to twist it to get it off.....You could always try to use some kind of inner flap over the hole and fit and weld on one of those fold open doors from brand X vehicle.....Of course you will still have a small bump out past the body to get your finger in......know what kind I mean? Or if you have to cut the neck back into the trunk and put a whole flush mount setup on from another brand x vehicle and just attach the two with short piece of rubber hose