Hi Tom,
I have a 43 with a Telstar keel as well and have done this. I have a two-piece prop shaft with a cutlass bearing in a strut. The first thing we had to do is unbolt the flanges holding the prop shaft pieces together and remove that pillow block bearing. Next disconnect the shaft seal. And last, remove the bolts holding the strut in place then take the strut off. If you simply want to replace the cutlass bearing you can stop here, but the shaft slides out on one side of the skeg (port side, I seem to recall).
As a side note, I understand you're in the process of replacing your pillow block bearing. It was also frozen on my boat when I got it. In the process of replacing it I determined that the bearing that was in there wasn't really designed for this use. It could take movement along the direction of the shaft, but only a few millimeters. When I looked at how much the engine would likely move on its mounts I determined this allowed movement certainly wasn't enough and contributed to the destruction of the bearing. In addition, the fibreglass holding the support board holding the bearing in place had broken free with the strain. I could just imagine the engine mounts moving a little then all the force of the turning propeller being taken by that little pillow block bearing on that little 2 by 4. So I replaced it with a truck carrier bearing. Something like this (probably not exactly what you need, just to give you an idea):
http://www.class8truckparts.com/Spicer- ... oCHWPw_wcBWe powder coated the bare steel so it would last longer and it hasn't given me any troubles since.
Mark