Belt diagram for 2000 silverado 1500 5.3 liter,

Diagram courtesy of AutoZone.com

I hope this helps.

The belt has tension applied to it from an idler pulley arm. you need to release tension by using a socket and ratchet on the nut on the idler pulley. Release tesion and slide belt off . Make sure you have the diagram for serpentine belt. it is usualy under the hood. If not make a diagram yorself before removing belt.

go to the dealer the parts department can show you on the cumputer

Here's the serpentine belt diagram you asked for...

here is an image of the engine in question (on the right) it is not a diagram but shows the track of the serpentine belt

http://static.howstuffworks.com/gif/1999-2000-2001-2002-2003-2004-ford-mustang-5.jpg

THE A/C BELT GOES ON AROUND THE COMPRESSOR AND THE CRANKSHAFT AND OVER THE TOP OF THE TENSIONER.

PULLEY ALIGNMENT.WITH BELT ON LOOK AT THE PULLEYS FROM THE SIDE.U MUST HAVE A PULLEY THE IS MISSALIGNED

You should have a drive belt diagram under the hood somewhere above the radiator, fan shroud or possibly on the bottom side of the hood near the latch.
I could'nt find a diagram for your particular vehicle.
Hope this helps.
Regards,

click on this link, and scroll down to 5.7L

http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c152800ba71e