Do you have a picture?

For the earlier trucks, 48-54, they are the same rear spring hangers (all 4 of them) from 3/4 ton to 2 ton. Which means they're real common.

I'm not sure if 58 is still the same?

•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-