IBM 3380 disk drives / info?

Among my pickups over the weekend were a pair of these HUGE IBM 3380 drives. Couldn't even begin to find room for the entire unit with its cabinet and controllers, but did scavange the drives and motors out of the cabinet. Biggest drive I've ever seen. Belt driven! from an external 1.5 HP motor ..these things are Big! Cast alluminium housing w/14" discs, the whole assembly seems about 1/2 the size of a V-6 auto eng! IBM site has several references to them, circa early 80's I gather but they sure look older than that. What I'd like to find is IBM publication #GC26-4491 [IBM 3380 Direct Access Storage Intro] and/or IBM pub #GX26-1678 [Storage Reference Summary]. Neither seems to be in the on-line library from IBM. Any other info or dating is always welcome too. Thanks, Craig