The problem I've found with the High Z Mod is; you're still limited by how far the spindle can travel down. You can move the gantry up, but then the spindle can't reach all the way down to your base(spoilboard). I was wondering if there is a plate you can attach to the Z gantry that would allow you to mount the spindle lower, beyond the lower edge of the C-Beam? Something like the Double Wide C-Beam Gantry Plate, but for the XLarge Gantry Plate...so a Double Wide XLarge Gantry Plate. You could just mount it on top of the present XLarge Gantry Plate and attach your spindle to it in a lower position.
Read through the High Z Mod for Lead CNC. Within the first couple of pages you see how to reverse the axis beam to where the whole beam moves which allows the spindle to go all the way down.
