A pain indeed. I've kept the board anyway and it's now in the spares box. Problem is with a non-working non-diagnosed board is that it could be ANY chip, so if you do use it as a source of spare parts for a fault, who'se to say the IC you labouriously desolder from it is in a working condition anyway. On a spare rainy evening I might have a crack at seeing if I can ID the fault.
The VIC board on the other hand seems to work well. It's in very good condition so I think I'll use it to substitute the board in my Collection VIC, which doesn't look half as pretty due to fixes done
when I first started collecting. I was not as deft with the soldering iron then.
. More importantly, this new board seems to recognise cartridges whereas my existing board does not! I only realised this when I tried the cart obtained in the haul. So a hidden fault existed which is now exposed.