Hi Ed,
We replaced our mattress early on with a Tempurpedic. Before we close the slide, we pull the mattress slightly away from the head of the bed and lift the bottom. Then, as we pull the slide in, Larry continues to hold the bed while I make sure the metal bars that support the bed frame during transit line up. We've installed a U-shaped piece of sheet metal to keep the bar on track. Prior to this, the wood was getting quite worn due to it not lining up quite right and I supppose from the bumps of travel.
Hope this helps.
