I am planning on building an upholstered bed using Ana's chunky leg bed frame plan. I would like to use my box spring and need suggestions on how to modify the plans. I see this was done here but I can't really tell what was done. We have a split box spring that is 9" tall, so I will probably need to use 1x10's or 1x12's. Can anyone help me with how to modify this plan to support the weight of two people, a mattress and box spring?