Yeah, slotting the whole column dosent sound like a good idea to me either. It would tidy up the conversion, but that's about it. I've CNC'd 2 of these machines. The first one was done from scratch, and I still have and use the machine. The second one was done with the CNC Fusion conversion kit. If you need to get it done right away, the kit is a fast way to go, but there were several issues that bothered me about that kit. The z-axis ballnut block covers the gib adjusting screws, which was the biggest concern. To adjust the gibs, you would need to unbolt that block, at which point you had no way of moving the head to see how tight or loose the gibs were...poor design. His thrust nuts were also a bad design and I told him a few times. They are simply a large nylock nut, which loosens in no time. I cross drilled and tapped them for a set screw.
I dont have any pics of the z motor mount online, but do have one of the X and Y. Notice that the table can extend out over the bearing block. That was another issue with the CNC Fusion kit, there was a plate in the way that took quite a bit of travel off the Y, and worst of all, there's no reason it needed to be there, just how he designed it. I explained these issues to him, but never got a reply.


I eventually took the handles off as I was sick of them catching on things and me if I got in the way.
I believe that these pictures are when I was still using the ACME screws. That was short lived. I bought used C3 class ball screws off ebay and fitted them in. That required redoing all the mounts. The screws were (and still are) in excellent shape. The Nook ball screws and nuts are also sufficient for this machine with steppers. If you go servo, I would probably use precision ground screws.
I'll dig up some pics of the Z or just take some new ones later.
I sold the machine with the CNC Fusion kit about a year ago. I built a 24"x24"x6" servo driven steel router table that rendered that machine useless in my shop. It's a shame to have a reasonably good cnc mill sitting there, never getting used. I hope the new owner is using it.
Paul