Are you Bruce Jones? I did a search for Zeus80 and came up with a page about the SDS VDB-8024 VGA modifications.
http://retrotechnology.com/herbs_stuff/sdvdbmod.html
Did you make an entire computer or just Z-80 processor cards? Your story is very impressive! Its really hard to prototype boards for weels on end just to have a computer. The current generation that I am a part of can't sit still that long.
Of course, for a lot of people in the early to mid 70s, if you didn't make it - you didn't have it.
Thanks for the post!
Grant