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What is the final torque recommended for a 1937 120-C with a cast iron head?

If the studs are threaded 7/16-20 I'd torque to a final 60-62 lb-ft. As usual, go in three stages and retorque after an hour or two of running, and then several times thereafter until they no longer require any take-up. And recheck again at the start of the following season.

Follow the factory pattern for tightening, or if you can't find it, start in the center and spiral out from there.

Thanks. The head is in place and shows no evidence of any problems, but I have a good torque wrench and I think it would be prudent to check it. I'll set the wrench at 55 and go over all the nuts in order, and if nothing moves I'll go to 60 ft lb and go over it again. The engine was painted some time in the past, and there is no evidence of any tool marks on the head nuts, so it hasn't likely been checked lately. The gasket appears to be a traditional sandwich type gasket.