Hi Gorgar666
Danger - Your pin has 110VAC Line Current, operates Relays and Steppers with 48VAC, Lamps with 6VAC - current can kill people. Always toggle-off and unplug the main power cord when You work on the pin. ONLY plug-in, toggle-on, start a game when You NEED current for testing. Ask a friend to help - locate the 00-90 Unit - also called Match Unit - most likely it is in the Backbox - Your friend plays a game, You watch this Unit - everytime Your friend makes 10 Points: The Unit must step one step. Look at the axis of the Unit - some kind of a gear is mounted - in one position of the unit the gear opens a mounted switch - in next position of the unit the gear allows the switch to be closed. Through this switch current may flow to the Coil of the Alternator-Relay - locate the Alternator-Relay - a simple relay --- non pulling, the friend makes 10 points, the Match Unit steps one step and the Alternator-Relay is pulling --- the friend makes another 10 points, the Match Unit steps one step and the Alternator-Relay is not pulling and so on.
IF (if, if) the Alternator-Relay does never pull: Be careful - wear rubber gloves or use an wooden stick - PRESS on the armature of the Alternator-Relay - 1,2,3 .. seconds - up to a minute --- does the friend now see lites, makes 10 or 100 points - means manually operating the Alternator-Relay makes the pin to function ? Write about.

We live in different time zones - I am ahead of You, maybe 7,8,9 hours - it is time for me to go to sleep. Greetings Rolf
P.S.: Good stuff: http://www.planetarypinball.com/mm5/merchant.mvc?Screen=BOOK --- click on Bally 1976 Parts Catalog then scroll through the pages --- from here http://www.planetarypinball.com/reference/partsmanuals/BLY_Parts_1976/index.html#/96/ I copied the drawing.

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