You mention the fuel system on the "500" tractor in the photo, the answer to your question regarding the fuel injection pump on that tractor was built by German Bosch and is an inline pump. However all Case tractors around that era were factory fitted with again a German Bosch pump - but of the rotary design as standard on all of those tractors for the U.S. market as standard. However all those models that were desined for export to foriegn countries were fitted with the in line type fuel pumps. At that time the rotary design of pump was new and that was the reason for the diffent pumps being fitted to those tractors.
Hope that you cann follow this.
Alan T. Lewis