From page E-9 of instruction manual (found online as my Wonka is being shipped!). Can't figure out how to take a screenshot but there is also a diagram:
1) There are two pre-drilled mounting holes in the playfield for a mini post, near the left outlane (circled in red in figure E10). The post can be repositioned (or removed altogether) to make the game play more or less liberally/con- servatively. The most liberal post position is the highest (furthest from the player) of the two holes (making it more difficult for the ball to get to the left outlane). When the post is moved closer to the inlane/outlane divider, the game will play more conservatively (making it easier for the ball to get to the left outlane). The most conservative adjust- ment is to remove the post altogether. This is how the game ships from the factory, with the post removed. You will find it in the cashbox "goodies" bag. See the mini post removal or installation instructions below. Optional plastic plugs are provided for the unused hole(s) in the playfield.
2) The dual rubber, steel adjusting post near the right outlane (circled in blue in figure E10) can be repositioned (or removed altogether) to make the game play more or less liberally/conservatively. There is a mounting slot routed in the playfield. The most liberal post position is the lowest (closest to the player) in the slot (making it more difficult for the ball to get to the right outlane). As the adjusting post is moved further from the player, the game will play more conservatively (making it easier for the ball to get to the right outlane). The most conservative adjustment is to remove the post altogether. See the adjusting post repositioning/removal or installation instructions below.
3) The steel mini post, near the right outlane (circled in green in figure E10) can be repositioned (or removed alto- gether) to make the game play more or less liberally/conservatively. There is a mounting slot routed in the playfield. The most liberal post position is the lowest (closest to the player) in the slot (making it more difficult for the ball to get to the right outlane). As the mini post is moved further from the player, the game will play more conservatively (making it easier for the ball to get to the right outlane). The most conservative adjustment is to remove the post altogether. See the mini post repositioning/removal or installation instructions below.