Re: GAP AR-10 waiters.....
Sorry to hear, I've been there.
Two hours after I bolted the MST-100 into the US Optics reproduction mount on my correct serial number range Remington 700 with USMC contract barrel and USMC return smear stock with matching #'s, I got my property tax bill.
After spending 8 months putting it all together and without ever getting to fire a round through it I pulled it apart and sold the stock, scope & mount.