Alt upgrade

Add an additional wire from the large alternator stud to the battery positive terminal. This will lower the current going thru the firewall connector, which will overload when/if the battery gets low and the alternator charges at a high rate. Many posts about this.

This is good info, but be sure you either use the correct rated fuseable link, fuse or circuit breaker to protect the high current cable.

Spend some time reading the Madd Electric article. It's a good starting point.