Based on what I've read, I'll be a PSA lower parts kit, an A-2 rifle buffer tube with 308 buffer and spring. I'm going to try using a Rainier bcg after having Rainier match bolt to my barrel. Not sure of fore end yet as I'm waiting for clarification from PSA on whether this receiver is high or low profile, because the rear tab at the charging handle is 3/16" which is supposed to be high but I read another thread that quoted PSA as saying their recievers take low profile handguards, ????????