All I needed to know. Thanks!
I’ve been playing mix and match with this potential build. Building the barrel group first, then the upper and lower.
Hand guard selection has been a pain in the butt. Finding a good free float 9” quad rail has been a pain so I am going with the two-peice MI drop in quad rail for the AR-10. The minuscule difference in rail height of the Armalite vs the DPMS G1 isn’t much of a concern to me.