rim width

[Oldstuff]

I am in need of another rim for my 1963 Ford model 2000. When I measured it I measured inside width from bead to bead and it was 10 inches. Now that I am looking for another wheel I am assuming that is how to measure them, because I am seeing 10, 11 and 12 inch rims for sale. My tire size is 13.6 X 28. Am I measuring correctly?

Thanks Oldstuff

 

[locknut]

Yep,that's right.