[skyking]

NICE!
I just got back to the forum ( working 6 tens and driving 120~180 miles on top of that per day!) and find this cherry project, read through the whole thing.
If there is a way to get inside the shell while it is down, and simply stand up with it, you don't need any lift mechanism IMO. Make the 4 side latches automatic, like a catch that you set to toggle over when the bar goes past.
Set the latches to lock ( by gravity ), lift up, and click, click, click, click, set down on latches.
Reverse process is set the latches to open, (bungees?) lift up, squat down. Just another thought. I can draw something up for you when this job settles down.