Heads up - This may be really dumb, but.... We'd all like disk rears. Not enough 3rd Gen disk rears made. And those that were made aren't that good of brake from what I read. And 4th Gen rears too long - wheels stick out. Other rear disk brake options I see seem expensive, or difficult - so my theory/question..... Is it not possible to remove the axle tubes from the 4th Gen rear, have the tubes shortened, and re-weld them into place? Could keep 3rd gen wheels without disturbing look/rubbing tires, have disk rear, get posi rear cheap. I thought I read that the tubes were only welded in 2 spots, and that everyone recommends having the tube welded all the way around anyway. The axles in the tubes would keep the alignment while re-welding the shortened tubes in place right? Just a thought - I am certainly no expert, never even welded anything myself. Someone with experience tell me why it won't work.

This looks alot easier http://www.thirdgen.org/newdesign/te...reardisc.shtml
But your idea may also work.

A lot more work to swap axle tubes. You would also need alignment jigs so that when the tubes are welded back in, they're in alignment again. If they're out of alignment, you'll eat up bearings.

Yep, I've done just that, but as Stephen said it's a lot of work.
Don't underestimate a good set of drum brakes. If you're running 17inch wheels you can slide some pretty big drums on the rear. I know, discs are cool and all that, but at least you can have another option.

doing any welding on a rear runs the risk of warping the tubes. It is very important to keep it in a tight jig if you are going to be doing any large amount of welding. It's about like doing bodywork. You almost have to do it a small amount and let it cool to prevent warping. I suppose it is possible. sounds like a plan though. You might as well give it a shot and see how it turns out.

I'm checking into it - I certainly can't do it myself. I know rods have custom rears made all the time.

I just figured that, after adding up the cost to make a 2.73 peg leg 3rd gen rear into a 3.?? posi AND then spending $200+ minimum on the brake parts (jy parts as per the article in tech sect) to get a posi disk rear - it would be more cost effective to pay someone to cut and reweld an existing 4th gen rear.

I'll post what I find.

*** Afterthought Question - is there any difference in 3rd gen (1992) axles and 4th gen axles that would prevent from using the 3rd gen axles in the shortened tubes?