Awesome game, congrats. The ball won't fall out of the lower playfield if the gorilla is set up properly. Sounds like the spring for the return arms is missing or a return arm is broken, possibly both. One of mine broke and the ball started to fall out because the gorilla's arms would flop all the way back when the playfield was lifted. Marco has the return arms and spring, though the spring can probably be found anywhere.

http://www.marcospecialties.com/pinball-parts/01-14206.1

http://www.marcospecialties.com/pinball-parts/10-362

As for the targets, the one swinks listed above should work, though it's smaller than the original. The ones you're looking for are the same as the five in the lower playfield, I have not been able to find any.

You don't appear to be missing anything, I took a couple quick photos of mine to help you out. Use the schematic posted above when reassembling, it's actually much better than the one in the original manual that I went by. That stinks you had to order another arm, hopefully you needed some other stuff to make up for the shipping charge. Mine broke while playing, so I ordered two arms and replaced them both since the other looked like it could also go at any time. After years of banging a thin metal part against another metal part, these are bound to break.

You should find it a lot easier to spell C-O-N-G-O once those arms are fixed and not just flopping around all willy-nilly.

IMG_20140628_132634_026.jpg

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