Otto,
original 1950 tank.
I cleaned it out by both nuts and then rocks. Strapped it to my my tractor and also tossed it in my other truck bed for about a month. It was pretty clean when I was done, but I couldn't see every part of the inside. That first fuel filter was bad. The 2nd & third year change out had hardly any.
Todd


1950 Chevy 3100