well first put the thermostat back in it, it's just a bad idea to run it without, next check that the hoses (top and bottom) going in to the heater core are getting hot, they are on the passenger side of the fire wall. if they aren't then your heater core may be blocked, you can try unhooking the hoses and blast some water through them, it worked for me. as for the dial only working on one setting, check the heat resistor dodad. it's located under the dash of the passenger side of the jeep. it should have like 5 wires hooked up to it. it's held in with two 1/4 bolts. thats usually the culprit for that and a new one is cheap as hell.
