That ball count unit doesn't have a 6th position. See pic attached. I no longer have a schematic for this machine to check the game over circuit.

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To set for free play read this. Pic attached is from my Fun Land set to free play.
Gottlieb Free Play.
There is one switch that controls free play on a Gottlieb game. Set the credit wheel to zero credits (shows zero credits through the backglass). On the stepper unit there will be a notched wheel with a pin sticking out. This pin should have opened two switches only when the credit wheel is at zero credits. Adjust only the smaller of the two switch contacts (located closest to the backglass) so it's permanently closed (or use a jumper wire), regardless of the credit wheel position. The other switch should operate normally, and be open when the credit wheel is at zero credits. Note there may be another movable pin (with a slotted head). This is the maximum credits pin. Do not change the switch this pin contacts. Your Gottlieb game is now set on free play.

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