It's pretty easy given a vise, vise grips and a 5# sledge for removal and a carpentry hammer and socket for installation and some patience for both the R and I. That said it's also easy to mess up the ears on the slip yoke and/or pinion yoke by using a press or by overdriving one cap into the ears trying to pound the opposite cap out. As a mid-level shade tree who found those two caveats out the hard and expensive way, I'd still do it again but only with the vise and hammer method.

Mark the driveshaft so you reinstall it in the right alignment. Kroil the caps generously and leave for a cup of coffee or such. When you return clamp the yoke tightly in a vise, cap you want to remove facing up and flush enough so you won't be hammering right on the yoke but not so deep in the vise that it's noticeably below the top of the clamp. Then whale the bejeepers out of the vise with the 5#er, right next door to the cap and keep hammering the holy hell out of it til the cap starts to walk out. Once there's enough cap to grab with some vise grips set them on the exposed cap and keep pounding on the bench vise and pulling up on the cap. You could also reverse things up when the cap starts to walk out and clamp it in the vise and tap the yoke off. Repeat for the other three.

To install the trick is to tap it in with the smaller hammer and a closely sized socket evenly. Evenly. Smear some grease on the roller bearings to hold them in line, line up the cap over the yoke ear, socket on top of the cap and tap tap tap each side of the socket to seat it in as straight as possible.

Repeat for each. It's a p.i.t.a., but it's not real hard. If you want to shop it and have an alternate ride, though, you can save some money by just bringing them the offending yokes and portion of driveshaft.