TJ's 98 and older that have the slide controls on the HVAC controls have the cable controlled blend door. 98 and newer with the round knobs are vacuum controled..... 98's could have either, but of course jeep sometimes blurs models together so those years might not be exactly correct.
another note if you have been running radiator stop leak through it that crap will plug a heater core and sometimes a radiator in a heartbeat... been there done that on my XJ trying to get home and sprung a leak.
