IT is top left corner and no, it does not go out as far as you think it might.
Here is an exercise for you:
With the slide IN, feel over the top or side edge, You should feel where the flat surface is.. Get your hands out of there and run the slide out
you should see this spot within a quarter inch of the fixed wall (If you run it out part way you may be able to peer over the top of the slide out and see the seal)
The motor (Assuming it is a cable car) is in the part of the room that does not move ABOVE the slide out if I recall correctly. (Been a while since I accessed that one)
A common battery powered drill or screwdriver with a flexible extension shaft is the "Tool" to use for Manual" override of the system if you have to.
Home is where I park it!