Gasket dry has worked for me if mating surfaces are smooth. Or a little black RTV on the gasket if surfaces are rough works fine. RTV only can work but not really recommended.

With RTV it is best to install the gasket and torque lightly. Let the RTV set up for an hour or so then full torque.

If you do use RTV it is important that surfaces are oil free. No seeping lube anywhere and clean with lacquer thinner first... preferably several times.