The bed in my van is a full size and measure 74″ x 54″. It’s plenty big for stretching all the way out without touching the sides of the van. I’m 5’10” and it’s perfect for me. The first part of creating my bed was to create two supports on each side of the van.
With the supports installed, I used 3 2x4s to create the bed platform. I finished it off with a full size slat system that I purchased from Ikea.
The supports fit into ares that I built onto the supports. It’s really a strong support and the bed feels nice and solid.