I have a '59 Apache 6 cyliner. The original tank was removed when i got it and I have replaced the gas tank, sending unit, filler neck, pump, and installed a carb kit.

I noticed the lines smelled like varnish so i used some paint thinner to try and cut it. It seemed to work pretty good and after I replaced the pump Iused the starter to turn the engine over. I got a good stream of gas and noticed it was pretty dark.

Is there anything I can use to clean the varnish out now or maybe some additive to get this thing going?