After a fire.....

If you want to reroute the alternator and/or battery feeds, that's up to you. Done well, it will result in less resistance to flow, which is a good thing.

You are referring to the battery feed going through disconnect and to ammeter?

If you want to eliminate the ammeter, that also is up to you. I encourage you to install a voltmeter on a switched circuit if you do that.
How would you wire a v meter and have ammeter? In series?

Whatever you choose for rewiring, it would be prudent to:
First check for ground short in the main circuit - including the alternator.

So you're saying a ground short inside alternator could have caused the fire? Interesting, but the wire from alt to firewall , while melted up near disconnect, was OK close to alternator.

Second, incorporate a fusible link on the battery feed.[/QUOTE]