Yes, all sorted now. Dealer hadnt really understood what was going on until he saw the dental floss pictures. They're going to replace the tank at the 600 mile service. ☺ Thanks for your help.
No, the fuel cap bolts go through a plastic clip/spacer and straight into the aperture on the tank. If aperture on the tank isn't straight theres nothing that can be done other than fit a new tank as @graemewalker said.
No not them. Wouldn't be fair to say now, they've admitted they missed it and have done everything I've asked for it to be put right too so I'm happy.
Ask em if U can have the old Tank. With a Race Filler Cap fitted you'd never know and could then sell on Fleabay for a few Hundred!