Mustangs did not come on to the scene until mid 64.
A carburated unit, so, anywhere up til circa 73.
Could not see how the front engine mounts were handled. Important element.
The SBF is narrower than the SBC and as such fits better.
A project, Tantalizing, not that far from here. but,no, it can not be…
In a S3, the frame rails prolly would allow a quad-cam 427!
Increases the temptation!!! But, it can not be…