I had one apart the wire is probably fine I put some shrink wrap around we’re it goes through the motor housing and when you take it apart there are the brushes just like the starter that you have to be carefull with as they if I remember correctly they have springs behind them .I also put a little more grease at the two ends were the bearings are .If it is running okay and not noisy the easiest and (no opening of the can of worms) would be to cut the end off and slide some shrink wrap down through the motor housing without opening it up then put a new terminal on the end .I think on Dave’s tec net site he he’s a heater motor that he took apart to use the housing to put a newer 12 volt unit inside using the old housing ,there may be some pictures that shows the motor apart that may help with your decision to open it up .
