So I had some more time yesterday and a little today to work on the 40. I got my rear 3rd back and put it in but had some clearance problems with my pinion shaft spacer. So, as Cruiserdrew suggested, I took out my axles and ground them down a little, which gave me just enough room to slide the spacer in. I used a little gun blue to mark the top of the axles so I could see how much i was removing and to make it as level as possible. Worked pretty good.
After those were in I buttoned up the cover. More progress is a good thing.
FYI: For anyone looking to POR15 your frame, don't get it on your bolts. I wasn't thinking and POR15'd my axle when I was doing my frame which in turn got all over the nuts and bolts for the diff covers, which basically turned it into a super form of locktite. Pain in the ASS getting the bolts off. Pretty much all but 1 of the bolts came out of the axle housing which then they had to be cleaned up and reinstalled, which sucks too. Now I just need a little spray paint and I'll call it good.
With that done I could finish putting on my rear disc brakes. I originally had the brackets facing the front but decided I liked them better facing the rear. I am having one problem though and its driving me crazy. The clips that go on the calipers (Monte Carlo), I can't figure out how they clip on!

I looked online and tried to find some pictures of how they clip on, but no luck. I know it will be obvious once someone posts it up, but I can't figure it out.
I went ahead and put the calipers on and put the wheels back on to see how my backspacing worked out, perfect. I do have a problem w/ the pads contacting and resting on the rotors, but I'm assuming that once I figure out the damn clips, that will take care of that problem.