A friend of mine in Arkansas is working on a truck that I am trying to help him with by phone. here is the story. The battery went bad. They put a new one in, and learned at that point the alternator was pumping out around 16 volts! They replaced the "box on the firewall" (voltage regulator), but report there is slime coming from the "two boxes on the drivers side fender" next to the orange box. I am sure this used to be a lean burn truck, but there is no computer, so I can only assume it was converted. It has been over 5 years since I have messed with an old D series truck, so I am asking for help in knowing what to check next. They pulled the alternator and had it checked. The amp gauge does not work either (has not in the past). First, what to check next, and I think the "two boxes on the fender well" are the starter relay and horn relay,,,,,, IIRC. He replaced the voltage reg, and it still pushes 16 plus. Anything else he needs to check?