I use a slide hammer as well. I have had a couple that where just impossible to get out. In that case I used the nut on the slide hammer like a puller. Take a block of wood with a hole in it across the gimble with the slide hammer through the hole then tighten the nut.

The center race of the bearing has adjustment. If it is not aligned you will know it trying to put the drive back on.

Nope, The center part of the bearing will need to be aligned also.

It is strongly recommended that anytime you pull your drive off the the boat you check the alignment, So that you are sure everything is still aligned correctly and that the engine coupler is well greased up also, Or you risk a engine coupler failure or even a bearing failure, Among some other things that could go wrong.

You could have a hell of a time getting the driveshaft in without aligning that thing first - especially as you struggle to get everything lined up and the shift cable on, etc....

It's a well spent $30....

As said before