Having done just this same job a week ago, I don't think I'd like to change the rear drive assembly on the road. Most of it uses basic tools found in your bike's tool kit:
T25 to remove the rear mud flap
17mm lug wrench for the rear wheel
8mm allen for the brake caliper
flat blade screwdriver to remove the clamp on the rubber boot
Here's where you'll have trouble. You also need:
16mm wrenches for the trailing arm
30mm socket to remove the rear drive pivot locknut
12mm allen to remove the two pivot bolts
gear lube and loctite
and zip ties are handy to keep the brake caliper tied up out of the way
That gets the whole rear drive assembly free from the bike.
Now installation is a bit more tricky. First, you want to align the rear u-joint with the front u-joint to minimize vibration issues, but you can't do that if you can't see the front of the drive shaft.
However, that's not as critical as the torque specs on the rear drive pivot bolts. You'll need a torque wrench plus a 12mm allen socket to torque the two pivot bolts correctly. The outside (fixed) pivot gets torqued to 160 nm, while the inside (adjustable) pivot gets torqued to only 7 nm. Then you'll need that 30mm socket with a special window cut out of it so you can hold the 12mm allen still (to maintain the 7 nm torque) while torquing the outer 30mm lock nut to 160 nm. The rest of the procedure is pretty simple though.
This is a pic of some of the special tools you'll need:
And this is a pic of how to properly torque the outer lock nut while keeping the inner pivot from moving:
Like I said, I don't think I'd like to do this on the side of the road, or in a parking lot somewhere. I suppose if you had the parts, special tools, and BMW Maintenance CD with you, you could get any motorcycle or auto shop to help you out. But the only way I'd carry all that stuff with me is if I was in the Iron Butt Rally and absolutely couldn't afford a day or so delay. I've had two rear drive failures on two different LTs, and both times I just arranged for a trailer to get me to the nearest BMW dealer and had the bike fixed within a day or two.
If you're still serious about this, I'd suggest you do the procedure at home in your own garage where you can afford to spend the time to get it right. I'd also combine that test run with a clutch slave cylinder swap
. Then you'll know if you really want to bother carrying all this stuff with, or if you'd rather just pack it all up in a box ready to be shipped by a friend or relative if needed. Besides the actual chance of a failure is pretty low, unless you're on your way to CCR.
Hope that helps.