RTV high heat sealant for water pump fittings?

I’m in the process of putting back my top end of my 383 engine and I switched over to an OEM style aluminum water pump. When installing the heater hose nipples, temp sending unit and anything that screws into the water pump and touches coolant how should I seal them before installation? A little rtv high heat sealant on the threads or some Teflon plumbers tape? Any suggestions appreciated.
Carl