Plates, try the same junk yard, otherwise they are expensive from GM, I asked about them a few years ago....

Longer studs, perhaps, and if so then might was well do the machine work and use 9/16" studs.
NAPA among other auto parts places has the studs and nuts.

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-