I wasnt sure if the ball was getting stuck beside the hole or just in front of the hole, on the gate...kinda hard to tell with the upper playfield off. So I had a piece of molded plastic cut out from a battery package:
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Then with some heavy duty double-sided tape, I taped it on the gate:
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and on the plastic to the side of the hole:
IMG_6633 (resized).JPG
Then as the upper play field was put back in place, it slightly bent the molded plastic down, so when the ball goes to that area it bounces off of it into the slot in the play field and runs to the lock stitch/ejector. I had limited time, so its a quick fix, but so far after about 25 games it has been working like a charm.
The worse part of the whole job was to make sure you don't gouge the play field with the ramp bolts that run through the play field when removing, handling and reinserting the bolts through the play field. Otherwise, the job was completed in an hour.