third hand tool for square or threaded racks

This was designed on a clean sheet, but I was heavily inspired by Fabrion365's awesome design here:
https://makerworld.com/en/models/142669-19-rack-mount-helper-third-hand-tool#profileId-772979

Unfortunately I have a mix of square hole and threaded racks, so I needed to make a design that would work with both. To accomplish this, I placed a #6 machine screw thru the square pegs. This screw is small enough to pass cleanly thru the holes in a threaded rack without touching the threads, so it can just act like a dowel pin to keep the third hand tool from sliding down. While adding the screws does enable the tool to work with both square hole and threaded racks, there is also a downside: because the screws stick out from the pegs by about 3mm, this means that every time you use the tool, you must move the slider an extra 3mm in/out. And actually it is even more than an extra 3mm, because I made my pegs a bit longer than Fabrion365 did. This does not matter much for occasional use, but if