As said (by some) just me I would not use RTV or TRS in that app, too much scraping to get the RTV off if you think you might be swapping pigs soon (most wouldn't be tho) & with TRS I'd about wanna put a nut on em & drive out the studs before attempting to scrape that stuff off. with cleaned surfaces expecially at the base of the studs, that a dry gasket would suffice, maybe a premium superformance one & even lubeing the gasket if frequent changes are anticipated. You do have a fairly wide contact area there. #1 check for debris.