The spacers can be changed around a little but the clamps may need to be changed to match. I think (but am not sure) that a given spacer works with several different tire and rim widths but on the same Dayton hub.
I was looking for spacers and clamps for mine, and was amazed at the huge number of clamp styles to choose from, and the several spacers available in different widths. Stop by a big truck parts place and have a look.

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-