I am talking light duty trucks here...cab and chassis models are completely different. Besides, Ambulances HAVE to have buckets so the person in front can get in back without having to get out of the truck and go around back (I am sure there are more reasons than this). My guess, is the buckets were added by the company who did the construction of the ambulances.
By the way, the rounded line series ended in 1991 (not 1987) with the Suburbans, Blazers, and crew cabs.
