[Gregw420]

1987 s10 2.8 bought new battery and alternater still no power from alternater to recharge battery . Running off just battery any help would be great thanks

 

[oldeerslayer]

Check to see if you have continuity at the power junction block on the firewall. There are a couple fuseable links there that could be bad. Also check that the small wires from the alternator aren't damaged somewhere. They control output.
And there's always the possibility these days you simply got a faulty alternator.
Here's the wiring diagram.