Where is the location of the PCV valve for a 5 liter?

Dear contrail1-- According to the boys down at AutoZone, the PCV valve is under the hood, center, upper engine area, mounted in rear of intake manifold. Good luck from Bovan.

I looked in that area but I don't see anything but hoses. Do I have to take the intake manifold off to get to the PCV valve?

no, there is a hose that connects to the pcv, it is in fact located at the rear center of the intake manifold on the back of the engine, you will have do do a little reaching to get to it