A Rear Drive X5?

[davintosh]

Yeah, that's a bit of a nonsensical sentence... the 'X' means it's all-wheel-drive, right? But reading threads like this one make me wonder if anyone has ever converted an e53 to rear drive. BMW's ///M division thought of it at one point, but decided against it. (link) Not that I would actually do it, at least not on the car as it sits now, but maybe later, when the car is worth less than it is now, and salvaged parts might be more available...

I'm thinking the following would need to be modified or swapped out with another model that is rear-drive:
Transfer case/transmission -- replace with trans from rear-drive car.
Driveshaft -- lengthen to reach the output shaft of trans minus the transfer case.
Front differential -- remove.
Front driveshaft -- remove.
Front half-shafts -- remove.
I'm not terribly familiar with the stability control electronics on these cars, but I'm guessing something would need to be done to keep the car from freaking out about the missing parts. I suppose DSC could be permanently disabled...

Why would you want to do it? Maybe to cut some weight & mechanical drag to improve fuel efficiency. Or if the car was older and lost the front diff, and you just wanted to see if it could be done. Or just to do it for the heck of it... Yes, this is mostly just a theoretical exercise, but just for fun, humor me. Ok?

Anybody else ever tried this, or have any thoughts on what would need to be done to make it work?