You can actually pick and choose which parts of the steamworks api to implement, so you can have trading cards, multiplayer etc without the drm side.
from memory, i think you do need to use the drm to use family sharing, we had issue with that when we chose not to use the drm, but everything else we could implement fine without it.
It really does depend on your cad skill level, but basically you would need to make a mounting setup to incorporate both. it is certainly doable, but tbh I would have a look at some cad files from existing setups, and what may be involved.
to be completeltly honest, it would likely be easier to use a Stealthburner mount for Ender 3, and build a Filametrix Stealthburner which incorporates the whole cutter and extruder into the toolhead, then just make some sort of mount for thr lever trigger. some probably already exist tbh!