Bob,
Thanks,

The pictures for the clamp plates are identical, but they show both plates, 10 hole, and in the background the 5 hole.

The purpose of the clamp plates are to add strength at the center of the wheel. The wheels are designed to use the clamp plates. I have used big washer face lug nuts without the clamp plates, but am switching back to using the clamp plates now that I know better. Mine are at the powder coater now, should have them back by the end of the week.

Ford uses the same bolt pattern and they use swiveling washer face nuts, but the center part of the wheel is nearly twice the thickness of our wheels, so they are designed to use nuts only, no clamp plate.

The original AD clamp plates have flat surfaces around the holes, and use tall nuts with flat ends, similar to what is used on the spring U-bolts.
The new style do have countersunk holes, and use chamfered lug nuts. I don't have an explanation as to why, other than it accomplished the same thing, but I do know they have no part in centering the wheel itself.

Someone else helped with the metric tire size part, and truthfully I have a general idea how it works, but I never bothered to really learn, as I don't plan to use any of those tires.
Sounds like I need to get edumicated and correct that part of the tech Tip... I know I have read a good simple and short explanation somewhere, now to find it again..

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
---All pictures---
"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-