What about this sticky goop in my gas tank?

[Lee Sumpter <leesumpter@xxxxxxxxx>]

Got the motor back in my 64 Fury, and it wont pick up gas from the
tank. Tried a new fuel pump, still no gas. Pulled the sending unit out
of the tank, and it looks like its covered with molasses! Now this was
a good running, driving car when I parked it, not some barn relic.
Anyway, time flies, and I realize it's been sitting in the garage for
6-7 years. I'm going to have to replace the pickup tube sock and the
rubber gasket where the sender goes into the tank. Whats the best
source for these items?
Also, whats the best way to clean out the tank? Anyone tried the POR
15 marine clean that's advertised on the POR 15 website? Or would it
be best to try to find a radiator shop that will still boil out a gas
tank?
How about opinions on the POR 15 tank sealer?

Thanks,
-- 
Lee Sumpter