It's probably a 351 Winsor not Wizard, and a Mach 1, not a Mark I
Lol well if he's calling it a mark instead of a mach and a wizard instead of windsor..what are the odds he knows what it really has in it? Mach1s of that year came with either 302 windsors or 351 clevelands..or the 429. Of course theres always the possibility someone has swapped engines over the years but that thing looks pretty original and appears to have not been moved in a loong time.