I modelled a little tab to secure the cutouts in place. Nothing fancy. You'll need 8 per panel. Thought others might find them useful:
Yeah, I'm not feeling the love at the minute, its dead in the water till a new stepper driver arrives so I can do the first extrusion test. And I can't get the z offset calibration at all. The Bed autohomes to 1mm away from the bed, the display TELLS me its 1mm away but when I try and change it the display says Err:Too Far! and wont let me. So close and yet so far On the plus side the build gave me the confidence to completely strip & clean the extruder hot end on my old printer which had a partial clog and now its printing the bits for a second filament reel holder like a champ.