Hello, happy to show you how to make one, I can not sell mine as sense of balance is slipping. The 60.s Swallow, Watsonian etc had a flip top with a side door for passenger access. They were 1" ash frame with a ply skin and covered with alloy, I used fi/glass. There were also full body chairs with full size door.  Chassis is also important more on that if you need it. Paul.