OK. Followed the sign Nazi link and read up. Not interested in interfacing with this individual. However...
Where can I find corrugated plastic sign material? Need something a minimum of 4 feet wide and white on one side.
Did find some at Lowes Depot but the price was a bit steep.
Try Wrapture graphics. Any sign shop can get it. But it'll be expensive no matter how you slice it to punch holes in.