may wanna PM Travelin2. He's the one that added a disconnect to his driveshaft for towing. He's prolly got more experience with the driveshaft than anyone.
You could also PM Marlin. He found a cupla VXs in boneyards & could help you contact the right person.
Billy's right. You may only need to remove the driveshaft & take it to a specialty shop to be balanced. Then reinstall with new U-joints.