Blackstone would probably call the EPA if he sent a 51 year old "oil" sample to them.
What would he learn by an analysis like that? All they had back then was non-detergent oil.
I'd almost guarantee it looks something like this. This is what my intake area looked like after it was opened for the first time in 64 years, and my engine was run regularly all the way until 1991. So you can only imagine what his engine could possibly look like inside. Again, any of the flathead guys here would implore the OP to look inside that engine, especially if it has set for 51 years.
Exactly... I don't know what the plans are for the engine/truck, but there is very little chance that running it as-is won't cause damage. Pulling the intake is pretty quick and easy, and will tell you a lot.
What is the purpose of the big clamp on the oil filter casing?