Customer asked us to quote signage for the attached frame. The sign from the previous business was apparently made of plywood and deteriorated to nothing so they pitched it. The frame will fit a 5' x 6' sign. We've used ACP for signs attached to walls, posts, frames etc. but never something that would be hanging in a frame like this. I would think that 6mm ACP would not hold up well in this frame. I'm also thinking 3/4" MDO would be too heavy. Honestly don't even know what kind of brackets you would use to attach the sign to the tubing frame. There is some chain and brackets still hanging from the old sign, but I was thinking you'd want to use something more rigid. Any help would be greatly appreciated.