it's a 4 ÃƒÆ’Ã¢â‚¬Å¡Ãƒâ€šÃ‚Â¾" bolt circle diameter, if measured from stud across to stud it's about 4ÃƒÆ’Ã¢â‚¬Å¡Ãƒâ€šÃ‚Â½", I usually measure the radius, from center of stud to center of wheel and multiply by 2.
Your '62 has a 4.75" bolt pattern. The way to measure is from the back of hole to the center of the second hole.
It also has 3.75" back spacing, which is important when purchasing new wheels.
15" wheels work out real nice on these cars.
Good luck with your project.