Some box trucks have fiberglass wall panel, one shot, no split. Some have 48" strips of thicker aluminum mounted with adhesive, no rivet. Some (most of 'em) have limited quantity of rivets and usually they are a li'l bigger and finally the aviation-type like this one which have rivets every 2" and rows are at like 24". In my area, there's a lot of fiberglass-like box trucks and 53' dry box. Signshops' prefered...