the 68 1602 is still only touching the top of the blue mark on the gauge. New 80 degree thermostat,new water pump,heater core and block flushed out and radiator flowing well.Can't figure out why i can only get the thing to come to the top of the blue even after driving and idling in the driveway for a long time. The heater only blows luke warm too. ??? any ideas?