Okay, so the drawings in my pictures above represent the way I THOUGHT the spring should be turning. In actuality the spring turns the opposite way, i.e. when it heats up, it pushes the choke closed (clockwise from the viewpoint of the picutre), when it cools down, it releases it (counterclockwise) to fully open position. It looks like I need a new thermostatic spring that winds the opposite direction.
I picked this part up at Autozone, and it was just a generic replacement for a Carter carburetor, and this one fit so I assumed it was correct. Does anyone happen to know the correct part number, or someone who would have one? I think if I get that, it should solve my choke problems.