Where Is The Thermostat? 99 Silverado 4.8l

[GnatGoSplat]

Thermostat seems to be stuck open on my truck w/4.8L V8, it warms up slowly and my heat only gets lukewarm on really cold days. It also never gets completely to normal operating temp when it's really cold out.

 

Usually the t-stat is in the upper radiator hose inlet on the engine, so I followed the upper rad hose and saw the inlet appears to be 1 piece with the water pump. I'm not seeing any way to remove the upper inlet from the water pump. Where is the t-stat on this engine? How do I get to it? I've been searching Google most of the afternoon to no avail.

 

Pics would be really helpful too.

 

EDIT: Could that be it at the lower radiator hose neck? I see a flange sticking out, with an empty hole and a bolt next to that.

[redvett]

Its just below the belt tensioner on the LH side of the engine.