I have supercab XLT, cloth 40/60 rear seat. Is there any way to get the rear seat back to fold forward so I can access the space behind it (looks like there's about 3 inches between seatback and back of the cab). Will the seat back move, or is it bolted down?

That's storage space for useful stuff (like rifles) not being used now....

 

The seat does not fold foward, but it is very simple to access the space behind the seat. All you have to do is lift the seat straight up. It is connected at the sheet metal on the window (3 connectors) and 2 connectors in the middle of the seat. The connectors are like little grooves which the seat slides into. I've used this space for tools, supplies and now the motor for my rear power window.
If you are creative enough you might be able to use the space in the seat as well. (When you take the seat off you will see what I am talking about.)

 

Kaution: Thanks... perfect place to store stuff. A power rear window? Did you design it yourself?

 

The Window was ordered from the Ford dealer. It was about $550 with tax I think. Then my brother and I took out the old one and put in the new one. It was much easier then I anticipated. It took us about 2 hours (of course this was the first time either one of us took out a window) And now its so nice being abable to open and close the window while driving.