What thermostat you run should be a 195. How is your engine temp??? Flush the rad or heater core lately and also check the cables are actually moving the valve to open up under the dash.
89 2.5 TBI, 4" RC lift, 1" Booms, SYE, Adams Driveshafts front and rear, Ford 8.8 with 4:88s, BFG 33X12.50X15, and a ton of other stuff.
AF Jeep Club Tail Number 184