"Fleet" is police, taxi, fleet, optional 65A alternator. There is a LOT of discussion on this board and others about bulkhead connector/ ammeter wiring failures, most particularly, with larger alternators, and the factory optional 65 alternator is somewhat proof that Ma knew this was a problem. In effect it is a form of bulkhead connector bypass, as the terminals in them are limited for current
Also read this:
You don't have to do this in this way, and if yours is in good shape you may not need to, but kit is food for thought