how do i take the gear shift knob off a 1995 celica with auto transmission and overdrive?

Floor or column shift? Floor shift should be threaded, column shift should have a split pin at the base.

It is a floor shift and it is not threaded. Apparently there are two small screws that have to undone and then it's supposed to just pop up, but that isn't happening. The screws are undone and I can move the shifter up an inch or so and then nothing. What do I need to do now to get the shifter **** off?

Did you remove the screws or just loosen them?

removed the screws.

Have you removed the center console yet? I used to own slightly older Celica GTs. The one with an automatic it was just as you say, 2 screws and off it came. But mine didn't have electronic overdrive. Does the shifter **** twist? The wiring for the OD button may be what's holding it up. You may need to twist it 90 degrees and pull the console so you can disconnect the wiring.