I don't believe that is a john deere 237 picker. Looks like a new idea unit painted john deer colors. Not too familiar with new ideas but I know that is not a 237.

Let's start at 6500 and go from there..what's it worth?

on the back itself has a new idea tag that says 315 model.....so is this whole unit a new idea?

That most definitely is a New Idea 319 gathering unit and 315 sheller. Someone sure went to a lot of work to paint it up in John Deere colors and decals as well! Actually looks pretty good - never seen one like that before! A 60 tractor is going to be way underpowered to do any amount of shelling with that rig - should have at least a 70 under there.

And I would be nervous having any mounted picker on this vintage of John Deere tractor with the "window" castings on the rear wheels. They only had those during the first year of production and soon switched them out for a heavier casting as the first ones had trouble breaking.

If you bought the unit lately it's worth what you gave for it.  Highly unlikely it's worth $6500.  Sorry.  Mike