I'm trying to figure out which is the correct PCV valve is for my 67 SS 350. The AIM shows part # 6422294 as the correct PCV valve for my application. Is this similar to either the CV-726C (6421934) or the CV-590C (6422721) PCV valves? I've seen thes listed for sale on line, and the PC-509C is advertised for a 67 Z-28, and I've seen the CV-726C advertised for a 283 Camaro. They are quite a bit different looking, so I want to make sure I get the correct looking one for my car. Are either of these an accecptable replacement for the 6422294 valve? They appear to have different size nipples on the end for the hose to connect to. Any help would be appreciated. I just want to get the right one.