Due to my almost pathological need to make my own version of everything, here's my direct drive mount for the Ender 3.
Bolts onto the x carriage wheels in place of the spacers. Should be pretty solid; I'm getting pretty good results so far.
Should fit the stock extruder; I'm using an aluminium one but the dimensions seem to be the same.
You will need an extension for the extruder cable.
Fang in the images is https://www.thingiverse.com/thing:3264588
Use at least 4 walls.
Print sideways with the extruder plate facing upwards using tree supports (see pics)
Once printed and cleaned up:
remove filament, the hotend and extruder completely, disconnect the bowden tube completely.
remove the top two wheels of the x carriage
remove the spacers. This slides on top of the x carriage and fits in place of the spacers on each wheel.
Reattach the wheels and adjust the eccentric nut until the carriage moves smoothly but doesn't wobble.
fit the extruder and motor onto the mount.
feed a length of PTFE into the hotend and measure out the depth.
using this measurement, cut a length of PTFE to fit between the extruder and hotend. I'd recommend cutting it slightly too long then measuring how much you need to cut off.
Fit the ptfe onto the extruder, then push the hotend up before screwing it in place.
Attach cables; there are grooves in the cable tidy for cable ties.
Feed in filament and enjoy printing.