I have, I think, a 68 Cougar air cleaner snorkel. It seems to have an engineering stamp C8WF-9A626 ? Could be wrong about that and it may be C9 ? The dimensions are the same as any 68-69 390 Mustang ? Mounting surface is at 5" centers so too big for a 428. Over all length is 10.25". Any info to share would be appreciated. Thanks, Brian