up here, 1973 was a transition year.
>if the car came with slanty, it got the small bolt pattern
>If the car came with a V8 and disc brakes it got the 4.5bc
>If the car came with a V8 and all drums....... IDK
If your car came with Rally Wheels, it's east to tell;
> the early sbc Rallys had a small centercap that resembled a Mexican Sombrero.
> The later BBP Rallys had a bigger and IMO, more attractive cap that was notched around the lugnuts.