They look pretty well built, but again, how much will that mess up the driveline angle. According to ORD's site, a shackle flip with the stock shackle should put the pinion on the axle at a good angle to use a CV shaft. I would think that with the extended shackle you would have to shim the pinion down to correct this. I would think it would be better to just get some springs to get the extra 2" of lift, but that is just me... /forums/images/graemlins/thumb.gif