Resolved Grand daughters 2003 3.8 v6 overheating

[Rck]

Rented a scanner from AutoZone. Engine heated up to 210° while gaude showed normal. My infrared readings only showed 180° at sensor and 190° at thermo housing. Temp cont to rise even after fan started. I shut off at 220°. Interior gauge stayed at normal.
Lower hose NEVER gets hot at all nor does rad cap.
Has new head gaskets, water pump, thermostat and temp sensor.

 

[Rck]

I know you folks are getting sick of this.
I can not find anywhere that explains how the scanner gets the real time coolant temp. They all say there is only a head temp sensor that is not in the coolant flow, which I know.
They explain engine can be toast prior to temp gauge showing hot. Also known.
Where is this magical point for the ECT then?

 

[Mustang5L5]

It does appear the 2003 V6 uses a cylinder head temp sensor instead of an ECT.

 

[Rck]

You guys have been awesome. Problem with overheating solved.
Head temp sensor solved it. But since I had drained radiator the day before and did not bleed air, it got better and worse. Found a thread on a different site that said to fill antifreeze with the car on a ramp or jack stands. The 2002 ford v6 loves to trap air. Also, the no spill funnel is a must. I improvised but got a ton of air out.
Scanner is no help if you do not have an actual coolant sensor and have a head temp sensor. Real time readings don't match up.
Thank you everyone for the input!!