I bought my 69 340 Swinger new,, it was built in late 68,, and the front bench seat didn't have headrests..(69's had headrests), and had the nasty camshaft..
I was running either F or G stock,, 7 inch slicks,, I was running 13.29,, and was 2/10ths off the NHRA record of 13.09, and somewhere I have the hardware.. lol.. IIRC..