I know I could be wrong but here is what i am thinking.
I dont have the axle right in front of me so please bare with me a little.
I was thinking that you would take some half inch thick steel something really strong.
(I would leave that up to the welder what kind of metal, but something damn strong.)
then sorta cut out a template from the end of the axle (allowing enough room for the wheel of course) and then following it along to the diff then cut it down to about a half inch until you get to the other side of the diff. Theh of course match it up to the end of the other side of the axle.
Once you have your template made out of cardboard, then trace it onto the sheet of 1/2 inch steel.
Then take a plasma cutter and cut out your trace.
You basicly create a long bridge that is welded to the housing of the axle, welded long way so you have the strength. From left to right all the way, in one piece.
Make a solid bead on both sides of the bridge.
Then around where the shock mounts are on each side you would run a steel reinforcement over the top and run a bridge over the top of the housing and pumkin as well. Left to right.
It is really hard to explain with out using Autocad or something but hopefully someday I will put my hypothisys to the test.
I will make something on MS Paint tomorrow and see what you metal guys think.
Using basic physics if you hit a rock, or other hard object instead of that portion of the axle taking 100% of the stress, the stress would be distributed evenly across the entire bridge, thus eliminating the possibility of a single 2, 3, 4 or even 6 inch piece of steel axle housing bending on you.
I think it would have to be created equal on top as well as on bottom, or teh physics may not work as formulated.
Like I said before you would lose an inch of ground clearance on the tube, and a half inch under the pumpkin.
If you can find (or are) a master welder you may be able to create a bolt down lip onto the diff cover for both top and bottom.
This would create an awesome skid plate that would not go anywhere unless the welds failed on the bridge.
You would have two extra bolts holding the diff cover onto the diff as well. 1 on top, and 1 on bottom.
When you need to remove the diff cover, you would remove all the bolts and then grab the cover from the left and right side and pull it past the bridge bolt housing structure things and straight out. Kind of in a groove, so that when you put the cover back on, it would align back in the groove, then the diff cover would have something to rest on while you are rebolting it back on.
Get it?
Done.
I think it would be cheaper than swapping to another axle, but would create a really sturdy housing and diff structure.
If only you guys could see the image in my head.
We really need to work out the whole Matrix idea like on the movie.