I'm trying to remove the heater from the cab but no luck frown

So far, I have:

1. Removed the heater hoses.
2. Removed the remains of the defroster duct work.
3. Disconnected all wiring.
4. Detached control cable from heater unit.
5. Removed six bolts securing heater to inner cowl,(both front AND back of heater).
6. Removed two nuts from engine side of firewall attached to heater support bracket.
7. Removed gasket from around blower motor.
8. Inhaled rust, dust, dead insects, and mouse droppings.
9. Put a new "twist" in my back and neck

But anyway, I can now get it to move about 1/4" up and down, but there still seems to be SOMETHING thats holding it up. Does anyone know what that could be? I haven't been to aggressive with it yet because I don't want to break something else, but I'm considering a crow bar next. grin