Recapped the worst looking IIcx board first. I didn't try it before hand as I was told it being totally dead. After recapping it starts up fine but no chime from loudspeaker or headphones, no video, no disk activity.
The corrosion on pads was pretty bad and I two caps fell off during the initial wash. It was pretty difficult to find some clean metal but I managed to do all electrolytic SMD caps. I guess there are some broken traces as well.