I need to replace a cracked magneto post. I see the three screws on the base of the post. I want to make sure there are no nuts on the bottom of those screws that will fall into the transmission when I unscrew them. Are there nuts on the bottom of those three screws?
no, threads are in hogs head.
Great. Thanks. Should I put any gasket sealer under the gasket?
If you have a good gasket no sealant required. Methinks Henry never used it on Ts.
A used fiber/cork gasket should get some sealant. If new, then maybe a touch of cup grease could work.
Concern is also not use too much twist to fasten down those 3 tiny fine thread machine screws, easy to strip, and if you bust one in the hole, hard to get out. So new gasket, sealer, and gentle screw down is better for this type.
That opening at the top, where the oil is really slung by the flywheel/magnets can leak, sure, Ford used felt gaskets, but back then, nobody cared about oil pouring on dirt roads Today the expectation is a fairly drip proof T, or neighbors won't let you ride up into their driveways
Now, the Improved Car has the best seal, a copper crush ring can be used, no sealant needed on that for the screw in type magneto contact base.
Ford used some sort of Soda based sealer on the mag post installation at least for some of the years. I remember seeing it on some drawing or record of change.