Never replaced the Ultra-tec bearings but I have replaced many bearings in my lifetime and the technique will be the same. First check to see if anything is holding the bearing in place, C-clip etc. If so remove them. If only pressed in you will have to drive the bearings out. On a dual bearing setup it can be a little tricky. There are pullers to remove such bearings sometimes specialized one but most can be driven out with a punch and chisel from the inside. Just punch a little on alternate sides a little at a time. Best to install new bearings with a press but one can use the old bearing and hammer to install the new bearing.