I saw a statement somewhere about putting the front seat down, to carry a long piece of lumber. I've leaned mine all the way back; but does it go down, forward, to lie flat? If so, how do you get it to do it!!?
Move the front seat all the way forward, take out the headrest (there's a little button on the side of where it meets the seat) and lay the front seat back. Take off the rear headrest, too, and fold the rear seat forward. Ta da!
It's not required that you remove the back headrest. I don't think it gets in the way. If you plan on haulilng things often, you might want to consider keeping a drop cloth in the cargo hold or the little cubby on the left of the back.