I've made several square cutter blocks (European style, sort of) by milling the slots for toolbits while mounted in place on the compound.
When milling the slots, shim the block up a distance equal to half the thickness of the intended toolbit, and use an endmill in the lathe that's a bit larger than toolbit size so there's a little room for packing under the bit to fine-tune it's height. Drill and tap for 2 setscrews over the slots.
Mine have two cutter bits per block, pointing in opposite directions. I usually put a righthand bit in one side, and a left in the other. Once I get the toolbit set to the correct height on each of the half-dozen blocks I made, I have a poor man's quick-change tool system--not indexable, but I never really needed that.