I had this problem when i first got this game, and after my shop job. Assuming I bent the metal slightly. Took off the right ball guide on the Davey Jones ramp and bent it so it was straighter. Where the tab to mount to the playfield is, I slightly bent it away from the ramp. This metal bends fairly easy, so be slow and careful. I also gripped the Davey Jones ramp real good and twisted clockwise.
Had to skim off a bit of the post rubber, but now it fits perfectly!
My full power plunge no longer makes it up the Davey Jones ramp, I think I may have to carefully bend the 2 ball guides in the launcher lane.
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