The center bearing needs to be pressed on/off. Supposedly position is sensitive and there is a volvo part/gauge to press it on to the right position.

Changing the universal joints is, well, universal! If you've done them before you'll do fine on the Volvo. Press off/on, using c clamp or press and sockets, etc.

One thing...the relationship of the yokes front/rear and to each other viz a viz the two driveshafts IS critical...you must not change it...generally just mark the driveshafts so they go back together the same way.