I am trying to restore a couple of 70 hp 440 motors and am short a few bolts The original ones are 5/16 and a little longer that a motor that does not have a windage tray. They have a number "23" on the head. Is there a source for those? What about the new one you can get from Ma Mopar/ I have not looked at the head but I know they are the longer version. They also have a nylon spot on the threads for locking I suppose.