Update/response to MAC1911's conversation query re; gunsmiths:
OK. Thanks for the input.
After conferring with some very experienced guys on a carbine board, I think I am going to go ahead and handle the most obvious aspects of the repair--and then proceed cautiously with a function-testing and inspection regime.
I might not be able to fix any problems identified--but I will definitely be able to competently alert the owner to any existing hazards.
I messaged back and forth with some very knowledgeable guys, and they suggested beginning with a de-burr, using a stone and oil, on both upper and lower surfaces of the lug races.
I have my own approach to addressing the peening pretty much figured out.
I have a set of headspace gauges coming in early next week, and a line on a couple excellent bolts. I'll decide which one when the time comes. After confirming headspace, I think I'll fabricate a bolt-lapping tool and scare up some dykem blue and just make sure that the bolts lugs have good even support. If they don't, if something is off with the receiver geometry and only 1 of the lugs is bearing the recoil, then that answers that. The owner has either a very expensive parts kit or a very nice wall-hanger.
Thanks again for the effort and the input.
All the best.
For bolt lapping, go to 7:35
View: https://www.youtube.com/watch?v=aMZjVJb0tRk