Cleveland Question?

Found a Q code 73 Mach-1 in a salvage yard. Not much left of the car, but
got the engine and trans for $325. When I got the engine home checked the
casting number on the block D2AE-CA this checked out, Intake manifold was
4bbl spreadbore. All seemed good until I checked the Heads. They had a 2 in
the corners, which means 2bbl heads. So you mean to tell me that someone
removed the 4bbl heads and placed 2bbl heads back on, and left the 4 bolt
main block and 4bbl intake. I guess this is possible. Was planning on
placing this in my 71 coupe and taking out the original 302. I guess my
guestion is, is this how you tell the difference between 2bbl and 4bbl heads
on a cleveland?

Thanks Dean.