I’ve always wanted to do one of these! A 6 plus, would not restore giving error 9. Measurement of the data lines between the CPU and the anti-rollback EEPROM showed failure in the trace going under the CPU.
Rather than pull the CPU and run a wire underneath some brilliant soul discovered you can get to that signal by digging down from the TOP of the cpu, through the Sdram chip. Then you just run a jumper to the signal on the backside. Here’s how it went:
And now it restores…
No More Error 9!
