A video that is no longer available showed how to inexpensively make your mattress longer when the slide is out. I can only find a picture, not the video. As you can see in the picture, he cut a piece of foam as thick and as wide as the mattress and about 6-8 inches deep. When the slide is out, he pulls the mattress down a bit, puts the piece of cut foam at the headboard area and then pushes the mattress back snug up against the foam. The cut foam will be under the spot where the pillows are and if the same thickness as the mattress, should be very comfortable. When the slides are going to be put in, he just puts the piece of cut foam on top of the bed and pushes the mattress up against the headboard. Hope that makes sense.
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