Classic/Antique Car Repair: replacing ring gear in 1939 1/2 ton chevy, bolts and nuts, rivet heads

Question
While attempting to find someone who could assist me in replacing an old riveted differential ring gear, the mechanic I was referred to indicated that cutting and removing the rivets holding the ring gear was not the problem, the problem would be installing the new rivets. Can the rivets holding the ring gear on a 1939 chevy 1/2 ton be replaced with special bolts and nuts, or do I just need to continue looking until I find someone with the knowledge and the right equipment?

Answer
Well, a couple of things. According to my best sources the ring on the 1939 differential should be bolted on. 1936 was the last riveted ring gear. My sources could be wrong, as it would not be the first time. The rivets are not a big problem to replace and they are done cold in a hydraulic press. I just went though my tool box as I had a rivet forming tool that I used in the press to form the rivet heads, but I cannot find it. I think the problem with nuts and bolts is the clearance between them and the pinion. If you have enough room grade 8 bolts would do the trick. On the Chevy rings that were bolted on they were safety wired at the factory.
Brad