Hey WVtradbow,
Was wondering if I could run one more questions by you. I recently continue on the old rebuild and now have the emt lifter panels both front and back. Also I do not have canvas on right now but am currently building that. Anyhow, the lifter build went great and I have everything installed. I use a pin to lock the lower and the upper emt together when the roof is in the up position. 
My question to you, do you use anything else to lock the extended panel in place? Mine can still pivot a lot at the bottom pivot point (where connected to the camper). I am not sure if once I have the canvas on, will that canvas be enough to hold everything tight, or do I really need to add some sort of arm or bar brace to stop the entire panel from pivoting back and forth.
Any insight you can offer is greatly appreciated. Best - Tim