Not trying to be a "wet-blanket", but if the two photos are a representation of the entire system, then it looks way too far gone to justify reviving. PCB traces are likely compromised in many locations and you'd have a very difficult time repairing them without special soldering equipment to remove the components (to get to the corrosion/trace runs that are likely broken). If the board is multi-layer (not likely in that old of a system), then repairing that would virtually be impossible.