what is the normal operating temperature for 2004 for 6.0 diesel? on 2004 Ford F-350 Super Duty

the vehicle cluster gauge is marking at about a quarter

2 answers
Engine performance good? Heater putting out good heat? What are your concerns?
Specs show thermostat should open from 188-192deg, fully open 219deg. That's the specs. Then #1 has good answer.