i have a 2001 silverado with a 5.3L, headers, throttle body spacer, k&n filter and 2 1/2 inch dual flowmaster exhaust and i need your help on what shilft point should a put in my truck with my new hypertech programmer that i just bought please,,, any suggestions will help alot thanks

Bring it to a dyno shop and let them play with it. They will have the fact of what works best instead of what feels best at the time.