I am currently working with a township to revise their wayfinding signs. What is everyone using for wayfinding material substrate? The problem I am running into is that where they want these located, they would need to use some sort of metal strap to connect them to the poles...any suggestions? Dibond is out as there isn't really a way to connect a bracket to the back without drilling through the material. These would be single sided...center mounted on a pole or post. Size would be 3'x4'...thanks for any guidance/info.