Norwalk 1863 mortise lock questions

[Pschiffe]

I am trying to repair a Norwalk lock Company lock, Patented July 2, 1863. Plese excuse me for probably not using the proper terms; I'm an amateur! The problem is that the 'tongue' wasn't fully extending, so I took it apart and found that the long ribbon spring was snapped. I've jury-rigged a solution, but it's not perfect.
I have two questions.

1. It wasn't exactly clear how the long flat spring was supposed to be sitting in the lock. Does anyone know of a diagram for this lock? I created an aluminum foil wedge to allow it to push back on the yoke. Works OK, not great.

2. What is the purpose of the v-shaped piece that seems to be able to pivot up and down? (see photo). I can't imagine why it would pivot, and I don't see it moving at all when I turn the door handles. Is it supposed to adjust something? I'm stumped!

Thanks for any insight anyone on this forum can provide!

1. Here are some images of Norwalk builders' lock mechanisms from their Cat. No. 39 (c) 1939. None seems to be identical to your earlier model and probably will be of little help but should at least you an idea of typical construction. See thumbnail.
2. Sorry, I have no idea what that pivoting piece may be for!

Pete Schifferli