I've done this with stretched springs for cage door hinges but the body springs would need to be clipped or tied because that one hinge worked its way out before you had it in the truck. Wouldn't want it falling apart as you drove down the road!Nice semi collapsible cage though. Take off the top and fold it flat. Nice vid though! leave one side of the roof hinges on and the whole thing would remain one piece if you fold the roof to the outside and pull on opposing corners and lay it up against a wall in the barn. Nice!
Dang it! forgot to add; use water pipe tube insulation if you don't want to scratch up your truck bed. Not making light of your vid just throwing in a bit of evolution.
