I will have to say....I just had a circuit board fail on my air conditioner. This is what it looked like. I had no idea there was enough complexity to have a circuit board like this for a measly little air conditioner.
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B