From: Mr.Monshroud (jnimark@ix.nospamnetcom.com)
Switch #1 is near the edge that controls the credits / free play.  
Put those all in the On position and that should set the game into free play.  

Switch #2
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                      |  1  |  2  |  3  |  4  |  5  |  6  |  7  |  8  |
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Cab Type: Moving Dx   | Off | Off |
          Moving Std  | On  | Off |
          Upright     | Off | On  |
          Not Used?   | On  | On  |
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Advertise Sound: Off              | Off |
                 On               | On  |
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Ships per Credit: 3                     | Off |
                  4                     | On  |
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Ship Increase:   No                           | Off |
                 Yes                          | On  |
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Continue Play:   No                                 | Off |
                 Yes                                | On  |
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Difficulty:  Normal                                       | Off | Off |
             Easy                                         | On  | Off |
             Hard                                         | Off | On  |
             Hardest                                      | On  | On  |
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