I have a 2008 Silverado regular cab short bed 4x2 3.23 rear gear with v6 auto I want to swap to a v8 my 08 is apparently different from the earlier models no one can reprogram the ecm/tcm no cai nothing for it. Even though it runs smooth it lacks power what year ls motor should I look for I want to keep my cruise and a/c my truck came with an electric fan are there wiring provisions for it to be run by the stock ecm/tcm thanks for any/all help