67 cuda FB progress UPDATE

:banghead:can anyone tell me what this spring is too?
I found it in a box of parts that were removed when we tore the car down.
I can't figure it out. If anyone knows and can take a picture of their spring and it's location I would greatly appreciate it.
I was thinking maybe it was for the brake pedal return spring but I think it's way to strong of a spring.

Looks like the one for the jack