I believe Triathelete replaced his U-joints a while back, maybe ask him how difficult the job was. You can buy new u-joints at indy4x for $40.

Which u-joint, transfer case or diff? The upper U-joint/driveshaft assembly can be easily removed from a Trooper and directly fitted to a VX. I paid $20 last month for an entire trooper driveshaft and the u-joints were in good condition. The top splined section is the exact same as the VX while main part of the shaft is too long. Definitely the cheapest way to go if you need to replace the upper U-joint...