Ford sohc 427 was offered as a OEM $2500(?) "dealer installed option" for many models (there is a 64 Galaxie here with one, the owner says the dealer was trying to get the State Police to buy them, didn't happen, due to chain problems)
They were mounted into some original Shelby Cobra's and GT500's (68' Shelby here with one)
Ford did Factory build atleast 10 Mustangs Fastbacks in 65' with sohc motors so the motor could qualift for NHRA stock eliminator class (Dyno Don Nicholson won a Summer Nationals with one)....
there were a bunch of (different) factory experimental (Ford oem blessed) A/FX cars built with sohc 427's (Gas Ronda did mid 8's at 160 with one) Phil Bonner, Bill Lawton, Dick Brannen are a few others....
so......was it a stock motor????.......kinda "fuzzy"....kinda like a Yenko?
here's the HP spec's on all of the 427 family:
and a few pic's
ps: Chrysler was woppin' Fords butt in the Grand National races was why they did it to begin with...it got outlawed pretty quick....so it became a "where else can we use one motor" that they had spent $$$$$$ to design and build