We installed a mild cam and intake. Tried to reuse the original rocker arms only to realize they were shot. Bought some flat tappet rockers from the machine shop only to install them and have them break on installation. Machine shop guy sold us roller rockers instead. We didn't know any better. Cue now and studs are coming up. We've been told threading is the way to go but still trying to decide. And slight ring wear is visible on the pushrods. We've pinned one of the studs but that's a difficult process for 16 valves. Any suggestions? We've been told mixing roller with flat tappet is bad for the valve train. Should we go back to flat tappet or what?