I know this is an old post, but I wanted to comment on the photos because it's lovely to see this classic hardware up close again. The giant chips and resistors, everything labeled on the board with codes.... so different then the itty-bitty stuff we see now.
In the 1990's I had a Gravis Ultrasound card that had a bad bank of memory. Upon visual exam it was easy to see that one of the traces wasn't properly connected on the board. A piece of tinfoil across the trace worked perfectly and the card worked fine after that.
This is a great overhaul of an Amiga, I'm curious if you did something to de-yellow the plastic, if it you just replaced the cover?
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