I am kind of confused with the complete build as far as keeping the grip together. The dial subassembly and the fuse assembly all have four holes to attach the screws through. The left grip does not have the two holes for the thread inserts to go. Am I missing something here? It just kind of looks like the grip will be loose when fully put together.

So, what was the verdict on this? In the files I have, the left grip contains the holes for the inserts. Should I actually use them or not?
I found that the 2 holes in the left grip actually caused more harm than good. The left grip is attached using the screw at the bottom. The left dial clamps it in place and the trigger keeps it aligned. Trust me, it works!