I am not familiar with your pop-up, however when you pull out the plywood, is there a leg under the plywood that drops down? Or maybe a cabinet door that you open to support the end that is floating in space?
2013 Jayco JayFlight 26RKS
2013 Ford F150 Ecoboost FX4
2003 Coleman Bayside / 2011 Jayco Jayfeather X20E -- RIP
2012 Tacoma Sport DCSB / 2013 Tundra SR5 - RIP