Are all sbp 7/16 lug nuts

Small bolt pattern ( 4 inch ) should be 7 /16 and big bolt pattern ( 4 1/2 inch ) should be 1/2 .
Usually the left handed ones quit in the early 70's , but its best to check.

One guy I dealt with , the repair shop swapped front drums on him , right and left sides , he broke
a couple of studs before he realized what had happened. Repair shop fixed it and got him new lug nuts.

Frank