Your trailer is a much earlier model than mine, so I can only guess.
It SHOULD be near the floor through the open door. Mine is on the right. Look for a wire cable with a loop in the end and the switches should be near that.
One switch should be the "master" and, if it's like mine, will have three positions. In one of the "extreme" positions, full down or full up, the lift switch will be active. In mine, you press the master switch on the bottom to allow the lift motor to function. The switch will stay in that position. Then, there should be a switch beside it that is spring loaded to the center position. If you press either the top or the bottom of that switch, and release it, it returns to center. That is the lift switch. With the master switch in the proper position, you should be able to push the top or the lift switch to run the lift motor. When the top is fully raised, you should hear a clank (the safety bar sliding into position) and the sound of the lift motor will change. Release the lift switch then.
Move the master switch to the opposite position to allow power to the interior (the lights, the water pump, heater fan, etc.)
The master switch has a center position that disables EVERYTHING except the refrigerator - that is the traveling position.
My lift switch is white and the master switch is black, but that may not be true in your trailer.
To lower the top, you have to have the master switch in the "lift switch active position", and then you pull the cable lanyard to release the safety bar. You may have to lift the top off the safety bar to be able to pull the cable. Then, just push the "down" side of the lift switch to lower the top. Once the top has started down, you can let go of the cable.
Hope this helps. I'll see if I can find the owner's manual for your model year trailer.
- Jack