Acapulco is Bally's second (and last) Magic Numbers game.  These games have a set of 2x6 numbers on a chain that operate in a similar fashion to Magic Squares.  These are disabled before you shoot your fourth ball or via the extended time tree, before fifth or after fifth.
On top of this feature, the game allows for up to 1200 replays on a single game, and brings back the Ballyhole (though it is not marked as such on the playfield).  
Several interesting and unique or almost unique features, a beautiful playfield, cabinet and backglass round out the package.