Can anyone please tell me or show a picture of where the radiator pressure relief valve is at in the engine bay for the HR?

Thank you.

 

As in the radiator cap? That's normally the "relief valve" for an automotive cooling system. Sometimes there are two caps, one from the radiator to the overflow tank and a second cap on the tank.

 

There is not one on the Radiator, the pressure relief valve is either on the water head in front of the engine block... or if you have a 370z de-gas bottle than it goes there with a blank off cap on the water head

 

The HR cooling system has a pressure relief in the cap right next to the oil dipstick. The overflow line goes to the plastic coolant reservoir in front of the engine. Looks like this:

 

Im pretty sure the pressure relief valve is located on the coolant hose between the firewall and the engine, you can see it behind the intake manifold, there's a plastic screw which you can loosen with a phillips screw driver

 

+1.

I remember I had to remove it when I installed the GTM TT kit.

 

That's a bleeder plug to allow you to get air out of the cooling system.

 

I got those mixed in my head.

So, yes its the radiator cap.