Econo-box housing Audio Injector
This 158x90x65mm Ebay junction box cost $4.39 us + shipping
try searching “Waterproof Plastic Electronic Instrument Project Enclosure Translucence Box” (the 158mm does not include the mounting ears)
To make things fit I caved away the waterproofing bead lands and cut out part of a post allow the Pi to nestle into a corner. Leaving just the Audio Injector outputs and MIDI connector to be chassis mounted.
All the Zynthian essentials fit, with the help of a sort of 2 in one with all the interconnect circuitry. you can get by with 6-8 GPIO connections with some ugly wiring to eliminate the 40 pin socket on the PCB.
It’s using those extra GPIO pins on the PiScreen to connect the encoder interface board, (except the 2 blue and violet interrupt wires going to the Injector’s GPIO)
Here’s the completed package (need better LCD fasteners) it was a tight fit, using header boards the Chines encoders came on, Cntrl 3 & 4 mount directly to my little hand wired board, which could have been moved to the right a few mm for better spacing.
There is an alternate super cheap case on ebay for $3.74 that is just 5mm shorter, it has no waterproof bead islands to carve away and no mounting ears.
158x90x60mm Waterproof Plastic Electronic Project Box Enclosure COVER CASE New
Someone with a small 3D printer could create a simple mount for the LCD, to slant it’s angle.