Thread Sealant for Coolant Parts?

RustyRatRod said
Doesn't matter. You use what makes you happy and I will too.

I did a search in the manual and it was not mentioned...pertaining to the two 3/4 inch, water jacket, pipe plugs in the /6 cylinder head...what type of tread sealant to use. Red RTV, Non hardening Permatex, hardening Permatex, etc.?
Norm