You are correct about the heads & the bolt hole.
The engine in my car has it & my mock-up head has it, I would have to look @ my other cylinder heads if they have it.
I believe it is the newer heads,like 1969 & newer that have them??? Not all do have them.
Why would this not fit in your engine compartment?
The super charger is not any taller than than a stock valve cover.
The supercharger mounting plate can be trimmed down,it does not have to be that far out to the side.
MBHD
