I finally got the gun and was able to get it apart (a challenge unto itself). I am not sure what measurement is important. The pin where the "c" part of the spring hooks on is .078" and the distance from the pin to the pocket where the spring sits at the lower part of the hammer is .390" when the hammer is full forward (toward the firing pin). Also note that it turns out the barrel is 16 gauge.

[img]https://photos.app.goo.gl/B9uqovpyUxdQzEwD6[/img]
[img]https://photos.app.goo.gl/RHcaEegTLhqZSi7v6[/img]
[img]https://photos.app.goo.gl/bVJAGg1AjbNyDC8U8[/img]
[img]https://photos.app.goo.gl/bVJAGg1AjbNyDC8U8[/img]