What housing do you have: the Chevy version with the round rear cover and crop-out center section, or the Dana 44 with a rear cover that looks like Home Plate?
You need to find out why that axle snapped. In my case, I had a Dana 44 ('62 Suburban), and just driving down the road it stripped the splines off one of the axle shafts.
After a lengthy process, I determined that the plug welds that hold the axle tube into the center section had all cracked, which is not uncommon at all. The cracked plug welds allowed the axle tube to have 1/16-inch slop at the housing, and almost 3/8-inch movement at the brake backing plate.
This caused the axle to bind in the center section (a posi unit), and eventually spun the bearing and killing the posi unit. The spun bearing killed the axle housing.
The GMC trucks were fitted with Dana 44 rear ends, and they're a direct bolt-in. The posi units were 30 spline axles. The posi units with 30-spline axles are still in production today. I got a unit from a new jeep and put it in mine.
I had to find another Dana 44 out of a GMC for a housing and axle. I've got one spare axle shaft, and the other with stripped splines. I haven't sent it off to Moser to see if they can copy or repair it, but they would be my first choice.
-Brad
