Hi, I have the rong fu rf45 (enco model 326-1832) just a few months old. It came with x-y DRO and I added z-- fairly simply with a rotory encoder on the quill spring screw. Had to upgrade to 3 channel ACU-rite. works great. Thought about head encoder but added lots of $ for very little application. I can copy my manual and send if the model is what your looking for.