4.5 bolt circle
It is 4.5".
5x5
4.75 bolt pattern.
I assume your talking wheel bolt size pattern, it's 5x5.
The standard bolt pattern (from the factory) for all Mustangs 1964 - 1973 is 5X114.3
the bolt pattern is 115/5. you can go to discounttires.com and find any bolt pattern for any car of any year.
2982-9345.
If you are asking the lug nut bolt pattern it's 5 on 4 3/4
The bolt pattern on a 1969-1991 K-5 Blazer is 6 on 5.5" (139.7mm).
5 X 4.75 (120.7)
5 on 4, and 3/4.