Simple. Once you get the driveshaft out, remove all the clips from the bearing caps if there are any. Sometimes they have some plastic stuff in them, you can tell by a little hole and maybe a blue tip thing and no clips. If you heat them up with a torch they kinda expand and come out like a worm coming out of an apple.
Once you get the clips off or those plastic things. If any clips are stuck, just use a socket and hammer and tap on the bearing cap a little and try to squeeze the clip together again and remove it.
Once you get the caps ready to come out, open your vise about 4-5 inches, enough to set the front yoke on top of both jaws and the driveshaft hand free, so you are catching the u-joint on the ends, then bang on the driveshaft right where the weld is and bang one cap out, turn it over and bang the other cap out, then turn the vise in some and lay the u-joint on top of both jaws and bang them caps out. Make sure you place the grease fitting hole so the compresses instead of separates when the driveshaft is spinning.
Set the u-joint in and gently place both caps on by hand as far as they will go but don't hammer them yet or you will loose the needle bearings and they will fall over. Now, set the u-joint exactly in the middle so it goes in a little bit on each end cap, then place in vise the entire thing between both end caps and squeeze it all together slowly. Then when caps are flush, if you have to put the clip back in use a socket and hit the socket with a hammer untill you can get the clip in.
remove u joint bearing caps
install bearing caps