Update
With the axle back together I turned my attention to the rear disc set up. I took apart the brakes on the AAM 11.5 and found how it was mounted and what fit together. I decided to make some new assembly brackets and not cut off the ones on the AAM 11.5 so that I could sell that axle for parts. I made a template, cut out new brackets from some 3/8" plate I have laying around, drilled the bolt holes and then took the brackets to a machine shop to have them cut out the center holes. The tube size on the AAM 11.5 is bigger than my 1980's 14bolt and I wanted them to get it right with more precise tools than mine.
Here are my brackets I made for my 14bolt compared to the ones on the AAM 11.5.
And here they are being tested on my 14bolt. The whole assemble bolts to this bracket.
There are differences in the hubs with the main issues being the backside of the AAM 11.5 hub being a different shape than my 14bolt hub. Same bolt patterns and the disc would physically slide over both hubs which is the way it is factory assembled.
Because of the differences on the backside my hub would interfere with the drum parking brake clearance. It may be possible to machine the back side of the 14bolt hubs to allow the clearance needed for the drum brake assembly so that the disc could be slid over the top of the hub like a factory install. Or it may be possible to use the AAM 11.5 hubs on the 14bolt spindles
BUT that will play with the WMS widening it from what I have. ALSO I found that the axles themselves are different lengths than what are in my 14bolt and I don't know if that was all from the hubs or if the axle tubes are longer and need longer axles or if it has to do with the positioning of the differential.
Anyways, I wanted to keep my hubs so I was left with either machining the back side down or just mounting the disc to the backside of the hub instead of the front. This is what I tested out and all it means to the assembly is that the bracket I made would mount further in on the axle. There is the necessary clearance on the back side of my 14bolt hub to not interfere with the drum brake parking mechanism with the disc mounted to the back of the hub.
I'm getting spacing and seeing where the bolts align with my mock spring in the way to see if there is a better angle to mount the assembly taking the bleeder valve in to consideration.
I made my choice and pressed in the rest of the studs. You can see in this pic that there is plenty of open space for the drum brake assembly on the back side of the 14bolt hub with the disc mounted to the rear. This means to replace the disc I'll have to pull the hub but since the rear doesn't get as much abuse as the front and since these components are overkill for my application I don't think I'll replace these much and maybe just once during the life of this rig. I did have the discs turned before I did final assembly.
With the test fit a success and the angles figured out I tacked the assembly brackets, pulled it apart, welded, cleaned up and painted. You can notice in this pic that those assembly brackets are not mirror images of each other. This is the same as on the AAM 11.5. So you have to set up both sides, you can't just set up one side and then place the other side at the same angle, everything will be off.
For me on my C&C 14bolt housing the original drum brake bracket got in the way of bolting to the new assembly bracket so I smoothed off the edges. If you are using a different 14bolt housing those original brackets may interfere completely and may need to be removed completely.
So here is reassembly after I muscled the 14bolt back under my rig. Backing plate bolts to assembly bracket and shoes are attached to the backing plate.
Then (for me) the hub with disc goes on and the caliper bracket plus caliper (not shown in this pic) is bolted on.
Then it was using the same brake line hardware (banjo bolts and brake line). Being on the cheap I simply resurfaced the pads since they had plenty of life left and used those.
I do not have the parking brakes hooked up yet to the cruiser cable. I plan too but I still have that line lock that I can use for parking.
As for driving impressions with those massive dual piston calipers I think (if I remember right) I installed the proportioning valve during that time and made some adjustments. Braking feels good and overall feels a little better than before but that may be because I can step on it a little more and not worry about the rear brakes locking up.