[66sprint6]

In looking at the engine currently in our Lemans (a ‘74 400), I’m seeing a few leaks. Some I can tell why, others I can’t. This is all preliminary but I want to be ready when it warms up to hopefully spend a weekend combing over the car and have it ready to be certified before we can register it for the road.
I’m seeing that the valve covers are leaking oil. Not surprising for an old motor. I was checking out valve cover gaskets and finding that they are available in 1/8” thick and 1/4” thick. Are the 1/4” ones for problematic leaks or does it depend on the engine?
Also, I’m seeing coolant collecting below the intake and valley pan. This requires further diagnosis, but I believe that it’s from the water pump gasket. If not, should I be looking somewhere else for a coolant leak?
Which is a good manufacturer to go with for gaskets? Is RTV recommended with a gasket anywhere in the cooking system? I’ll know more when we fire it up and really let the engine warm up, but I’ll take any pointers on what to look for with these engines.