I am almost done with the 351c and it really looks great [in my opinion] all of the stressed bolts are ARP and the regular non load bolts are stainless steel allen head. I can not find an alternator bolt in a stainless allen, the dimentions are 7/16 diameter X 6 1/4 long though 6" long will hafta due cause there not gonna want to make a 6 1/4.... 14 threads per inch. basically a stock sized 351c alternator bolt but in a stainless allen head- anyone know where i might get one of these ??