Ohio George Montgomery Mustangs

Yup!  These are gassers and not funny cars.

For years, Ohio George raced the gasser classes with '33 Willys cars.  He managed to get a factory sponsorship from Ford, so he dropped a 427 SOHC Cammer engine into his '33 Willys.  However, since the Willys wasn't a Ford, FoMoCo wanted more corporation association bang for their buck.  They insisted that with the Ford sponsorship, Montgomery outfit a modern '67 Mustang as a Gasser.  It had to meet A/GS class rules.  The Mustang was a unibody, so to comply, Ohio George used a full frame to enable running in the A/GS gasser class.  The '67 was his and the A/GS class's first modern vehicle Gasser iteration.  

In 69, Ohio George went with the twin-turbo Boss 429 Shotgun Engine.  My information is a bit sketchy here, so I'd welcome any correction, but I'm certain the car was making too much power and was sacked with performance-killing rules that made the car uncompetitive.  Ohio George switched back to a SOHC Cammer and carried on with that configuration.  In subsequent '70s years, Ohio George ran the twin-turbo again but as a funny car running on alcohol.