Moss Motors, Ltd

On the University Motors site, John Twist says, "We use a WHOLE CAN of rust prevention black goo on the top of the tank BEFORE we fit it!"  Any idea what brand of undercoating/rust prevention "black goo"  he is using?  I want to put some on my new gas tank prior to fitting. Thanks! 

Is there a trick to get the gas tank filler tube out of the grommet in the body?  Does it just pull out?  I have to replace my 1976 filler tube with one from an earlier year so that I can connect to the gas tank that has an angled tube.

Is there a way to modify the available gas tanks to fit a 1976 MGB?  The only tanks that are available fit earlier models, up to 1975 and have an angled filler tube from the tank.  Is it possible to cut the angled part of the filler tube on the tank so that the rubber filling tube will fit to the tank properly?  If this is possible, ...

What is the best way to get a replacement gas tank for a 1976 MGB connected to the filler neck?  The replacement tanks they sell for 1976 MGBs have an angled filler neck on the tank, and the rubber tube doesn't fit from the tank from the filler tube properly.  According to the Moss Catalog, the 1976  "tank has a short ...

Is it necessary to seal a brand new gas tank?  I just bought one for my 1976 MGB, wondering if I should before I install.  I had the exterior of the tank powder coated.