So it's been over a year now and the car is still starting perfectly. I still have a pretty large voltage drop in the bulhead connector even after adding silver impregnated grease to the connections but the car is starting and I'm good with it.
rich69rs - interesting document. It doesn't talk about the solenoid or the spring but changes the entire starter which includes both. I wonder if their changes affect the solenoid, the spring or the starter motor itself.