Hello everyone. I have a job coming up for three 4'x8' exterior signs. The client wants to have their info on both sides. They will be taking care of building the frame and support for the finished signs. They suggested that I use one board with signage on both sides. They want to support it with a post on either side and a header on top. They don't want to use any support at the bottom. My question to you is what substrate would be ideal to use for this. I wanted to use alumalite but I'm not sure how strong one board would be in the wind with just a support on either end. With similar signs I've done I used two boards with the support between the two. I received a suggestion for 5mil Alumalite today. Any suggestions? Thanks for the help!