I suffer from acid reflux and have to elevate the head of my bed 4". To solve this in my RV I removed the plywood platform from my bed. Cut a 2x4 corner to corner to make to 2 large wedges. Mounted them on top of the existing bed frame. Ran 2x4's between them to support the original plywood platform as required and remounted the plywood platform. The bed still hinges and opens like it use to so I did not lose any under the bed storage and if I sold the trailer I can easily restore it to it's original configuration.