Cables will overheat if they are not well tightened down or if the wires are not well connected to their terminal ends, both at the battery and the other end. High resistance at the connections is the cause of this overheating. Wires with good insulation crossing one another should not be a problem. Bad grounds to the cab and frame can show up as hot choke cables or throttle linkages. What did the ammeter indicate during this time?