I will admit,after researching the correct parts then hunting down all original vintage parts for my 601 and 602,when finally completed I had a "ok,big deal,now what attitude".It lasted a few weeks and during that time I actually considered selling them off as complete parts kits to include everything but the lowers.The feeling does pass,and I am still the proud owner of both.It is a shame that the only way to recupe build costs is to break them up and sell the parts individually.
I remember a local gun store back in the early-mid 80s had a couple of AR10s.I think they were Dutch.Price was something like $1200-$1500 at the time.I thought it was a bit hi,so I bought a PB BM59 for $650.
ETA,one thing that helped my attitude,,post pics of them as a family portrait,then sit back and read all the compliments from our retro family.