I am not entirely sure...
But I think the bigger AD truck clutches are called 10.5" and or 11", and they take a pressure plate that is held to the flywheel with 9 bolts. This is the clutch I have in my 1 ton.

I think the 1/2 ton clutch is a smaller disc, and fewer bolts hold the pressure plate to the flywheel. Therefore to put the big truck clutch in the small truck you also need a flywheel with the proper holes for mounting the pressure plate.

Hopefully someone else has confirmation or the right answer..

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-