I picked up a 2002 engine oil cooler with hoses for nothing, pressure tested it and its fine. It seems like a simple install into my 2003 that is missing this part, the oil cooler ports are on the front engine cover and the spot is open in front of the radiator. Why? Simply because I have the part and my truck is missing it, plus it can't hurt it.
So is it as simple as that and there are no additional parts missing from the front cover, like a valve or something?

 

Nope, simple as that.
You will need a extra quart of oil to bring the crankcase back up to full.

 

I figured that I would need to do that and I will do it at my next oil change, plus pulling the radiator out to fit the cooler in.

 

Let us know how it goes.