the credit unit

While I was in the back box tonight I took a look at the credit unit, since one repair I read about discussed bending it to be on Free Play.

Bottom left solenoid (the baby blue thing!) adds a credit.  The upper left one subtracts a credit.  When the cogged wheel (center right) gets down to zero credits, that solenoid stops having an effect, it is mechanically moved off at that point thanks to the rod sticking out of the brown plate.

Here is the machine with one credit in it.  Middle and right switches are closed.  I have no idea what that left-most switch does.  Perhaps it marks the credit maximum?  Seems logical...

And here is the machine with one credit.  The cogged wheel has advanced one, and the pole has hit the switch and opened those two.

I am unsure if you have to bend both of those, but really if you're going to start mucking up your machine you are probably best to consult an actualy reference and not some blog entitled PINBALL NOVICE.  So be warned.
But if they are bent for free play, one cool thing to note about this position is that a successful start-button press will activate the solenoid, but since it is mechanically disabled from the plate the pole will stay in that zeroed position.   That is opposed to, say, ramming it's way through the switches leaving carnage in its path.