i have a 92 full size chevy Xcab & i'm gonna do the big 3 trick. i checked out a good tutorial on big 3 replacemeny on sound domain, but got questions about alternetor to battery rewire. from alt. the wire goes to a block on firewall, but no wire runs back to the battery for charging. can i run a new wire from the alt pos post direct to the battery with a fuse of course or will this affect my electrical?