Yesterday I had a free afternoon so I dug into repairing the damage to the wires going to the two relay connectors. Each relay (high and low beam) has a four wire connector and they were all FUBAR, so the plan was to pull the wires out of the connector and solder replacments to the spade connectors, then reassemble. Then new wires were soldered into the wire harness on the tractor.
The spades are held into the plastic connector plug with little spring catches stamped out of the connector, so a thin narrow blade pushed into the end of the connector will release each individual connector. A pic below shows what they look like. In the past I've had some that were impossible to extract undamaged because they were so fragile. These are rather beefy, and I'm appreciative for that.
Once removed, the connector wire cannot be "uncrimped" without destroying the spade, so the strain relief wrap was pried open and the wire nipped off as close as possible. The connector was tinned and the new wire laid back on and held in place with the relief closed. Then the wire was soldered to the tinned area. Once all eight were done, the spring clip was checked to be extending enough and adjusted, then reinserted into the connector.
The mice didn't leave much room to work on the existing wires at the tractor, so it was a bit tedious working with limited exposure. The damaged wires were trimmed back, stripped and twisted with the connector wires and soldered. Shrink tube applied and heated. A couple zip-ties near the new joints would keep any stresses from reaching the joint and causing failure. Lights work- job complete!
I think I'll stuff several dryer sheets behind the dash while I have the cowling off, it can't hurt.