battery powered reciprocating saw along the sides where the blade fit, then switched over to an AC powered jig saw which also made short work of the sawing. There was some really irregular looking junk in the casting on the back of that channel you see (out of picture at top center) that I thought might limit the motion of the ballnut and table, so I cleaned that up with a grinding bit on my battery powered drill.
The next step was to take the motor and headstock off. This ends up weighing 50-ish pounds (rough guess). I found a guy on YouTube (N1BPD) who had a video of taking the motor and Z column off and then another that showed him building it back up.
It ended up being fairly cheap, because Mrs. Graybeard convinced me to try an adapter to mount the hex key socket on my 1/2" drive breaker bar. Thankfully, that worked and I was able to pull the Z column. This was right after I had watched the video where N1BPD built up his Z-axis and got it running. I decided I had all the parts and had been basically ready to do the modifications on this for quite a while, so why not do it and get the system running?
a lot about this part. The motor mount and standoffs were the parts I made for the original approach I was taking, before I switched to the ballscrew approach last April (I think). I think I made them about a year ago.