Help me pick an axle upgrade for my 'stroke
 

I have a 99 E350 van with a disc D60 rear. It started making noise at 95k and now I have diff fluid that looks more like glitter nail polish. I am planning on some engine mods but I'm holding off until I can get something a little more stout under the back.

Some of the SRW vans got a D70U, but it has the same basic configuration of bearings. It would allow me to swap in the larger carrier, but the bearings aren't any bigger. I've found other SRW rears that I could adapt relatively easily like an AAM 11.5 or 10.5, but they lack a place for the speedo sensor.

I need to find a Ford axle that is either SRW or could be made SRW with off-the-shelf parts that I can put in without too much headache. For instance, if there were a DRW D80 that I could use my SRW hardware and brakes, or a Sterling with the same width, or a .... You get the picture.

Basically, I'm looking to put a bulletproof axle back there that doesn't require calling Strange or Currie and spending more than I paid for the van.