Just did my 86 300E this week end, yes the rear seat and rear back rest must come out, also the head rest's must be removed, fist pry off the plastic peice that's on the deck, then with the rests in up position look down the hole, there is a lever down there that using a screw driver you push down on and release the chrome rest support lift the head rest at the same time. There is one in each hole (4). the side peices that the seat belt runs in also must be removed, they pull forward. (leave the belt conected). Just lay them to the side also in the first aid box were the bands hook to the little clips, there are philips head screws (2) that holld them down. The deck will be a little sticky when trying to pull up. It sounds like a major pain in the butt, well it is the first time. Make sure your out of the sun! and watch out for those 2 peices that the bottom cushion latchs too on the floor, they will cut your shines to peices. Good Luck, Chris C.