This is what it looks like under the carpet covered plywood. There two screws on the bottom of the angle iron where front of the screw shaft attachés, remove those and the Assy. comes out. You can buy the motor at Grangers for under 50.00
The two mounting screws are in the front angle iron that mounts the outer shaft driver and fits against the front kick step. You may or may not have to remove the step cover, that I have not tried yet. Remove the screws and pull the whole thing out. I read somewhere that the electric connection may be part of the problem. Your quote of 1200. seems nuts, I pulled ours out in ten minutes the first time. If you do what to remove the step cover there are about eight screw under the cover, three on each side and two that hold the limit brackets.
The cover is mounted to the rusted iron.