How handy are you with a soldering iron?
I'm mucking around with a OnStep open source goto system for an EQ3 at present - seems to do all the right things at this stage, although the weather in SEQld isn't conducive to testing outdoors at present.
Here is the link to the wiki - takes a bit of time to work it all out (well, it did for me) but so far, the system is working as described.
https://groups.io/g/onstep/wiki/home
DT