Obviously, I did not finish my project in time for the conclusion of Retrochallenge. Of course I'm a little disappointed, but in retrospect there's not much that I could have done to make it come together successfully before August 1st.
A few things went wrong: I didn't get my chassis back from the powder coater until over a week into the month already, and then my power supply died just as I was getting started. But even so, given what I've discovered in the CPU so far I doubt that I would have made it by August 1st even without those problems. In fact, I predict this restoration will take several months more at least. I'm fully committed now, I'm not stopping until this thing works, even if I have to replace every single IC.
I'm counting this as a valuable learning experience, and I'll be back with some crazy new idea for the next Retrochallenge.