Hey, I didn't think about it last night, but the intake manifold on a 6.2 carries no fluids, it's just a set of air pipes. There can be no oil leaking from the intake on this engine, the intake gasket is downright optional. Sorry I didn't catch that last night.
"Right Stuff" is very good gasket maker (can often be used in lieu of a gasket), Sets up in just a few minutes, and adheres well. The failure rate is low, but it is a pain to clean off if you ever want to reopen the sealed surface. Keep that in mind and use judiciously.