Are you sure that the light post can with stand wind loads if the
sign is attached?
Do you really want to see a lot of cars with dings all over them from
signs blowing all around the parking lot ??
Besides, regulations probably state that other than a 12" x 18" no loitering or trespassing
sign, nothing can be affixed to a light standard pole containing electrical wiring. They are light standards, not
signs posts.
Be careful.
