Removing Fuel Cap WITHOUT a key!

[old son]

I have changed over my ignition switch and all is OK. I was sure I had put my old key in my pocket but now I can't find it. I can't find my spare key either so I can't fill my fuel tank. I need to remove the entire cap but it seems there is a single bolt under the cap and I can't get the cap assembly off.

I have tried picking the lock, no use. I could try drilling the lock?

Would Yahama have a key number if they had my chassis number?

I am stuck at the moment, don't know what to try next?