Im a big fan of the permatex copper spray. I used it to install a new fuel pump on my 51. Spray both sides of gasket, spray block surface, spray pump surface, and let tack up for about a minute. Then spray gasket on both sides again and install immediately.
I find its hard to get an even coat of something you squeeze out of a tube. This was my first time using the spray, and I will now only use RTV for diffs!