I didn't realize Z-axis backlash is a smaller issue than X/Y -backlash. But it starts to make sense. Thanks for comments!

Right now, I will try to figure out exactly what to do, by studying other builds.

Perhaps will then come up with a "shopping list", and can start, and hopefully finish, too, my own CNC conversion thread.

This CNC -thing is such a fascinating, quite addictive topic Admire you folks a lot.