Hi Widget,
As for the acetone don't waste your time with that idea. I was at a mates place last night and the carby on his ATV ( it hadn't been used for many years) and it started dumping fuel on the floor. Pulled the carby off and pulled the float bowl off and it had a green film all over the inside of the bowl. Mate grabbed his bottle of acetone saying this will clean it up. After leaving the acetone in the bowl for 15 mins it did absolutely nothing
