I'm reading this thread and I have flashbacks - I started the same way, as you didi767, with an Ender3 and a Duet.
The first tihing I did after getting Duet up and running, I added second Z motor and lead screw, to get rid of Ender's sagging X-gantry issues.
After all my modifications, my Ender looked more or less like a some sort of Franken-Prusa, basically the frame was from Creality, gantry was
a Prusa X gantry and I had Ender3 bed. In the end I decided to build a closed COREXY and I have a Duet3, the
Creality frame is not meant for heavy-duty printing I think. The wheels need adjusting and the frame is too narrow.
