As a closer, Thx to you all for the great info. I got the tank out fine, used the spanner. Even the white worked great on the metal as a bore scope showed it to be nice and bright clean with rust gone. Then the problems began. after stopping the acid reaction with baking soda solution I rinsed with water while agitating / spinning for days checking the drainage which never seemed to become clear of the small rust particles ( stuck in baffles ). Never felt good about putting the sealer in in this condition so I bagged the whole mess and bought a new stock style steel tank with a larger capacity, a few extra gallons. I know some have had success cleaning and sealing the old tanks but I wish I'd
have done that from the start and saved myself the mess and time.
All good now, nice clean Sunoco Ultra getting to the engine.
Thx again for all the advise on removing the old tank
Tony