That Retrocal looks nice Brother...My 20" "retrocal". A/4 upper,heavy barrel,3 prong flashhider,m16 BCG,original A/1 handuards,repro A/1 pistol grip,LMT rear sight,A/2 stock,built on DSA lower with colt lower parts with a little duracaot added for fun.
My sons DTI carbine kit with unknown gun show quad rail handguard and foregrip built on an olympic lower.