QCTP Quick Change Tool Post
A QCTP is not just for setting centre height.
As they mount repeatably in the same place this is also in the same place relative to one another which you can use to advantage. Use a cranked right hand knife tool if possible so that its cutting point is exactly in line with the facing tool so after facing you do not need to reset your reference for the new tool. Then set the parting / grooving tool left hand front and edge to align with the knife too. Finally align your screwcutting tool for matching depth.
So for example you can face off, cut a length for threading then go straight in with the groove for screw cutting tool clearance, then switch to screwcutting all aligned to each other.
Finally if you set the cross slide index on zero with the tool on a known round figure diameter, eg 1/2 in and don't fiddle with it you know it will be at zero when dead centre. Then you can cut close to required size on the dial and only check for the final precision cuts.
It does however get rather expensive if you want to have every tool in its own holder.