Originally Posted by ala_xfire

Colt meter measures HORSE power, use a Volt meter, other than that Jay is correct.
You should see 12.2-12.5 off, 13.6 - 14.2 across the battery terminals when running.
From what you have stated a new alternator is in your future.
Make sure you get an SRT6 one, Limited has the 6 groove pulley.
( and make sure you remove the negative battery terminal before replacing it ! )