Truck running Hot??

[woody_1]

First, I want to thank eveyone for the help when I thought I blew the motor last time.Brian at BTS my hats off to you. I owe you big for staying on the phone and walking me thru everything.#7 injector and I found my IPR was bad and replaced it.
Now I have another issue.It started over flowing coolant out the fill tank on side of radiator.I started by flushing radiator and changing thermostat. I now still have it pressuring up that fill tank and over flowing.It has not ran hot.It will get warmer than normal ,but not Hot.It use to run around the R on the word normal now around the L.This is on the dummy gauge from factory.

Any Ideas what else to check? I also thought it could be a Head gasket is that possible?