I modified these from the original creators files making parts thicker to support a hole through center for 1/4 inch x 2.5 inch long machine screw and slot to insert 1/4 inch square nut. Ive included Parasolid files as well as Gcode, STL, and photos of my successful prints. I did have to do some mild filing off of support area to get good fit. These modifications will enable locking the Cope and Drag together and maybe use of 1/4 inch Eye-bolts so a carrying bar could be inserted. God knows if the parts will hold the weight. If you try this last part let me know your results.