If you have either 216 or 235 intake laying around, you will be able to see which one does or does not mate up to the exhaust. Also 216 intakes are straight, 235s look like a gorilla twisted them.
The 216 manifold intake alignment sleeve measures 1 13/32" OD by 3/8" HIGH, 235 sleeve is 1 17/32". So find either intake to determine what you've got for an exhaust.
