Maybe build on top of what @RoughDraft40 did, and “just” recreate the two 3D-printed spacers as machined pieces ? If you have long enough drill bits, it may just boil down to cutting two square pieces of wood manually and drilling two holes along their longest dimension. If you don’t, you could carve “thin” spacers on the Shapeoko and stack 3 or 4 or them ?
There is also this page,
which assumed you could buy the expansion kit from Suckit (and I think you can’t anymore?), but it does have the plans for the required ears (bottom of the page), in case they don’t come with the new HDZ (I’m unclear on that)