It really is that easy to grease the drive shaft (if you have a grease gun). There are three zerk fittings on the rear drive shaft. One at the front u-joint, one in the middle of the drive shaft at the slip joint, and one at the rear u-joint at the rear end. Plug your grease gun onto the zerk fitting and pump grease in until it starts oozing out of the u-joints/ slip joint. Actually, keep pumping grease in until the grease that is oozing out of the joints is clean. Wipe off the excess grease or it will get flung around under the VX and you're good to go.

One word of advise; wear eye protection and don't lay right under the joint that you are greasing. The eye protection is to keep all of the grit that will fall off of underside of the VX out of your eyes and you don't want to lay under the joint because the grease will fall off as it keeps oozing out and that stuff is really tough to wipe off of your skin (or hair).