New member formula S 1966

That's a darn cool car!! There are a few things I could point out...

The radio is an aftermarket unit, not available from the factory! The rear speaker is also not correct, it would not have a rear speaker no matter what radio you had! The radio you have does have the correct outer knobs tho, lending credence to a dealer install! The location of your speaker is the correct location for the rear window defrost if so equipped, a seldom seen option!!

Yes, your car would've come standard with a 7 1/4", 8 3/4" was an extra cost option in late 65 and 66, and would not have been standard no matter what drivetrain it had! The certicard clearly shows that is was ordered with a Suregrip and an 833 4 speed!!

I would love to see more pics in the clear daylight, it looks like a great find!!! Welcome to FABO, and the wonderful world of A bodies!!