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The saga:  The engine over heats at any time doing anything.
The list of replaced parts:  Fan clutch, thermostat, water pump, new 3 row all metal radiator, head gasket, suction side hose.

After the engine over heated the last time while my wife was driving, the plastic end cap on the radiator blew apart.  I put in a new radiator.  The engine overheated within a 1/4 mile after warming up.  I pulled the head and found that nearly all of the cyclinders had "cross talk" and it looked like at least one of them was getting hot gas into the coolant channels.  I replaced the head gasket (along with the manifold and valve cover gaskets) and let it warm up in idle.  It eventually warmed up to the point of needing the electric fan to help out.  Is this normal?  I bought this used and don't know what "normal" is.  I then drove it and managed to go about 1 mile before it started to approach the red zone again.

I've read that the 4.0l runs "hot" but what is hot?  Do they heat up as you drive faster like up to 65mph?  What is normal?  Does the transmission fluid have any effect on the overheating?  Remember, this heats up just idling.

I'm looking at getting a "long block" and completely replacing the engine if I can't figure this out.  The Jeep has 160,000 on it now.  Compression is still good, though, at 150 psi.  

check belt routing. have you bled the system? do the fan clutch and water pump have the R markings?  

most overheating with the jeeps is the pressure resivor + cap 34 dallors gets a new one  

Did you by any chance look for a rad hose collapsing?  

Wow, lots of choices! So I'm gonna throw another one in.

If this thing was overheated badly you may have a crack in the cylinder head it's self, if this happens it will push compression into the cooling system and the motor will become air locked quickly.

Put a pressure gauge on the radiator and without pumping it up, watch the pressure when you first start it, if the gauge goes up quick you have indeed the above problem.

Don't rule out the new stat, I've been there a few times.