driver side drop would be a Ford or Dodge 1 ton dually. Probably a ford, being as they were more plentiful. You need to specify the steering knuckle design (open, closed, high steer knuckle,) or snap a pic, that will help you sell it better. I know alot of guys got burnt buying the super dana 44's thinking they were getting 60's.

Edit: this is a perfect set-up for a straight axle conversion on a 88-98 chevy truck. especially if it's the high pinion dana 60.