ZMR front/back 5mm spacer

Upgraded my ZMR to 4mm arms and an integrated PDB so the spacer kit I had was no longer ideal. Decided to design a simple front/back spacer with adjustable height so it can be adapted to any scenario of arms + nylon washers (to avoid carbon fiber touching the PDB) or other spacers. I like the front/back spacers because they add support between the plates and allow LEDs to be mounted on them.

The uploaded version is 5mm, 4mm for arms and 1mm for nylon spacer, but the OpenSCAD file has the lig