Yesterday was a very good sleuthing day. I figured out improvements to the power connection on the USB-ified Personality card, so it should work with a glue chip rather than a fuse for improved reliability. I have a bunch of UCC3912 chips on order and can’t wait to try them.
Search for: "One of the issues affecting all areas of System Software". Then read on for the chronicle of horror! Eventually Apple solved the problem by delaying System 7 until 2MB Macs were the norm