Ac Actuator Part Number

[rexican]

Hello, I've had the heat stuck on in my truck for the past couple of years now . I've spent the last couple of hours going through threads about the actuator near the passenger floor board. What is the part number for this actuator?

I have a 2002 silverado 1500 LS 4.8l, single cab, short bed.

 

I tried replacing the A/C cluster to no avail, and I have no problem switching from vent to defrost, so I thought it must be that common actuator problem. It's starting to get hot down here in TX, so any help would be appreciated. This will be my third summer with the heater stuck on, I've just dealt with it up until now. I used to call it my personal sauna or the barbecue pit(its flat black).