I inlet the plate so its right where I want it, then the internals.
Much as Don S. describes. Sometimes I do it all with scrapers, chisels and gouges as was done here.
Knowing EXACTLY where the locks tail will be, for example, eliminates having it point someplace I don't want it too. Unless I screw up which I, of course, never do
I have a swivel breech in the works and have the lock plate inlet and did not even have holeds drilled in it until it was almost completely inlet. But I had to do this so I could get the lock back out. Will do the internals after I make the springs and get it functional. I think the store bought guts will work OK. I suppose I better start on that Monday and stop shaping the buttstock.
Dan