Glen, the thing that dings in under the dash to the lft of the steering column. Cylindrical thing about 1-1/4 diam and the same length. Cut or disconnect the red wire or add a switch to turn it on or off. Carefully pry up the bottom edge of the dash hump and the move it towards the windshield. The top edge will come loose. There is a defrost vent on the left end. A set of plastic automotive panel tools helps but the flat end of a spoon works too. Work carefully.
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In the big bay on the drivers side you should find an aluminum box on the ceiling. Carefully remove the cover, don't lose the screws. In one of the corners inside is a toggle switch. That overrides the transmission lock out. If you were able to drive then that is not needed but good to know about.
The level system light will be on and the dinger dinging for several reasons. Not at ride height, insufficient pressure sensed at the six pack controls, the auto level is still on and probably another that I am not thinking of now.
Bladder deflates. Make sure your compressor is running and/or the small HWH tank is charged. When you switch the key to delate air comes from the tank and the compressor to a manifold on the inside of the under slide carpet covered truss towards the rear of the big bay on the dr side. Air escaping causes a low pressure through a Venturi which sucks air out of the bladder. If there isn't enough air moving or the deflate solenoid is stuck then the bladder doesn't deflate. If you turned the key off, waited and turned it back on and th bladder deflated then probably you were short on air.
I added a pressure gauge to show pressure in the bladder. Inflated it shows about 12 psi and will hold for weeks. Another shows air pressure in the HWH tank.
Best practice on any slide (good job by the way) verify that the bladder is deflated. Closing a slide with an undelfated or under deflated bladder is almost surely going to damage it.
After 2001 the yellow light shows that a certain vacuum level was achieved. 2001 and earlier it is just on a timer. The 2002 controls are quite different than the 2001.