RatDog

Hey Pat - I believe GM began adding the seat belt mounting plates in March or April 1966. If your car doesn’t have them, the mounting plates come with the 3-point conversion kits. No welding required. The plates go up in the wheel well and are held tight against the backside of the fiberglass by the seatbelt attachment bolt on the inside of the car.

I bought my headrests and headrest mounting hardware from Al Knoch. They are quite pricey but I was thinking of the safety factor so I opened my wallet wide. You will have welding to do with the mounting brackets on your seat back frames.

My understanding is that, even though you could get leather or vinyl seats back in the day, you could only get vinyl headrests. Al has both. I got leather because I was changing my seats over to leather from vinyl so my car was leaving the realm of originality anyway.

Steve