Hi, an update on some things in this vicinity (just to make sure you haven't missed it):
https://www.facebook.com/groups/CommanderX16/
https://www.reddit.com/r/retrobattlesta ... or_battle/
https://internalregister.github.io/2019 ... BIeXNf_UlA
That last one is Z80 but still the video stuff might be applicable!
Edit: Videos that dig deeper into how to build your own computer from scratch:
6502 reverse engineering https://www.youtube.com/watch?v=fWqBmmPQP40
Make your own RGB video https://www.youtube.com/watch?v=uqY3FMuMuRo