I purcased a 396 block Friday, and the guy I bought it from gave me a set of exhaust manifolds that he said came off a bbc. The #s 10 221 882 & 10 221 881 .... 6D5 ... +GF+HE. Any idea what these go to? He also gave me a set of 4 bolt main caps with the engine, he said he was gonna drill it out for them. Is there a number on the caps that will help ID them. I am not goint to use the caps or manifolds but would like to pass them to someone that can. Also what is the best way to clean the main caps?