I know there was a 260, maybe a 289 in the car ( it is a 65 mustang after all) this guy has stock manifolds on a 5.0. I think he’s modified the front frame rails...look at his exhaust clearance.If there's a Falcon, the $400 K member converts the front end to Fox. The fabricated shock towers are pricey, but would be pretty easy to fab. ESPECIALLY now that we have an Amada 3kw ENSIS laser, a turret punch, and a couple of press brakes at work. And oodles and oodles of 11, 14, & 16 gauge sheet metal we run and tons of drops we scrap.
Even if I didn't do the Fox K member conversion, I notched the shock towers on a Maverick when I was 17 or 18. It's not rocket surgery. Especially nowadays if you finagle a coil over spring in there, could probably cut it 2" deeper than I did then.
If I go with an actual Fox, it would probably get a tubular front end, so the frame rails in front of the strut towers don't matter. The roll cage will tie into the strut towers to stiffen it up.
Is that full exploder front dress....accessories are wider than the engine. Looks like a MII conversion. That's pretty cheap too, but for drag racing, I don't think enough suspension travel.
You do realize Ford put Windsors in them from the factory? You don't have to cut the shock towers to put a Windsor in it.
Wait...let me re-phrase...
Look at his LACK of exhaust clearance.