Print the single unit, or the four parts and glue together. There's no allowances so you'll have to force them to fit.
Wind a filament around one knob, back and forth through the guides, and then wind it on the second knob. I used 24 gauge steel wire, but I suspect some heavy dental floss might also work. It was tricky to get the wire tight, so if you find a good technique let me know.
Push down through the SPAM to start the cut, then turn it over and force the wires through to complete the slices.