I would procure a piece of the wood, or a similar wood, with the correct thickness AFTER MILLING and use it to set the bed up the way you want it. Just reading the way Joe H has his set is not like mine is so there may be a few choices.
"Truckin' Around .......... Since 1937!" My name is Joe and I am addicted to Classic Country Music. I just can't hep myself. Operators are standing by to take your calls! Now cruising in the Passing Lane