Update 2018/02/13: Alternate Base with heat bed nylon support holder added back in.
Update 2018/01/28: Alternate Cover with clip to hold camera adapter.
This is a rework of Prusa's "Einsy-base" file from Github. I knocked out an opening to access the RPi Zero, reworked the vents, and added a removable cover. There is also an added slot to access the lower screw used to mount the base to the frame. The Pi cover is held on by screws commonly used on computer case fans, like these. https://www.amazon.com/dp/B01LLKY3GO
The Prusa original Einsy-base is printed in PETG, at .35mm. I printed mine in PLA at .2mm. Prusa Control sliced it beautifully. So no need to get fancy slicing. The MK3 really is an amazing printer!
Alternate Base: Originally I removed the nylon filament holder on the heatbed cable in lieu of extra vents. The nylon filament wasn't staying in place for me very well, and the zip tie seemed to be doing the job OK. However, there was a request to add it back, and it wasn't too much work. So there is now a "b" variant that has the nylon filament boss. The part has a "Wb" mark on the back, "W" for Rpi Zero W, and "b" for the b variant.
Alternate Cover: In order to use a camera with the Pi Zero, an adapter must be used to connect the mini camera cable to a regular cable. Apparently the mini cables all come in mini lengths. Most installs I have seen, including my own up till now, left the adapter just floating around loose. Couple with the extra 24" cable, the camera cable was getting would up with the X-Axis wire loom. This alternate cover partially fills in one of the covers slots, so a clip can be used to hold the adapter up out of the way, on the cover its self. This neatly folds up the mini cable, and points the longer cable up and out of the way. Adafruit is the only supplier I have found yet that has an adpater/extender to lengthen a camera cable with a Pi Zero. https://www.adafruit.com/product/3671
One of the pictures also shows a set of brackets I have published that routes the camera cable neatly around the X stepper, and the wire loom. This bracket is part of the RPi camera mount I put together, that uses Ball and Socket links to position the camera relative to the print head, on the X-Axis stepper. https://www.thingiverse.com/thing:2773810
Notice: License changed to GNU GPL, to match Prusa's original source license.