So I've finally gotten my Prusa i1 (yea... yea I know) working after a lot of work. I am printing the parts needed to finish it off such as fan mounts and in this case a ATX power supply mount. My problem is that the mount was too tall for my printer to finish. I had to stop after a layer had completed to avoid damage to the printer.
I know what layer I stopped on. How can I "slice" the gcode and restart from that layer from the z- home? I'm not worried about joining the parts with super glue, heat, or hot glue. The parts have to be functional, not pretty.