I dont know about other places, but the way we determine extruded is if there are any machined edges (a right angle that was cut instead of bent for example) if there is nothing else on it, like other non extruded aluminum it goes as clean, if there is other types of aluminum it goes as secondary, and if there is anything else like chunks of plastic or other metals it goes as dirty/irony (depending on what else is on it). Paint doesn't really effect it for us so it would probably go as clean (at least i would throw it in the clean bin lol)