Jolly Park has 2 for the upper playfield magnets.

Here's a couple other oddball ones that technically fit the bill: Dinosaur Eggs and USA Football (the flipperless version that isn't in the archive here). They both have 4 flipper buttons that are just about as "extra" as you can get. The 4 on Dinosaur Eggs don't do anything at all.... in fact they are immobilized so you can't push them. 2 of the 4 on the flipperless version of USA Football are for your initials and for moving the "DOUBLE TICKET" light, the other 2 are immobilized.

Alvin G used up old A.G. Soccer-Ball / A.G. Football / USA Football head-to-head cabinets for these two titles, hence the unused flipper buttons. Just an interesting piece of trivia, so I figured I'd list them.