Remove fuel tank liner

[colfax03]

I have an 89 softail and just had a new paint job that was power coated on. What I think happened, was the heat from the power coat process broke down the gas tank liner and I have been having problems running. I have removed the tanks and tried some acetone which helps but there must be an easier way. Balls and chains etc. don't work. Any help is appreciated.

Then I will have to re-coat the tank after I clean it up. Any suggestions for a product? Thanks

Colfax