On ours, the top board under the mattress was not nailed at all to the frame. Lower the bunk into the couch set up. Tilt, just the top board away from the frame and very, very carefully maneuver it at an angle so you can turn just that board vertical and take it out of there. Then you can see the two bolts holding the bunk in. Put something (a 2x4 under the frame so the bunk doesn't drop and remove the two bolts. Now, there is no way of getting the rest of the bunk out without removing the front and back trim panels. First you take out the screws and then (they are also nailed on) I pried those two edges off with a mallet and crow bar. Once they are off you can turn the frame upright and remove it. If you're careful your bunk can still be reassembled at anytime. I'm cutting mine down to go back into the same place, but it will be a 4-5 inch wide shelf all the way around!