Here's a custom game built around an orphaned running man unit. The running man unit playfield was replaced with lexan to show off the interesting bits below the playfield.

Baseball_Game_sm_(resized).jpg

More info including a video of the game play at: http://markgibson.zenfolio.com/fun-with-pinball-games (at the bottom).

/Mark

I've added scanned and cleaned up background scenery from a Williams Pinch Hitter to my website for anyone who might need it. I think it was used in other games too.
RoundedBacksm (resized).jpg
It's on the same page as the Running Man unit players I posted a while ago. They can be downloaded and printed.

https://www.funwithpinball.com/resources

/Mark

I recently finished up a counter top pitch and bat game with backglass animation, '47 Bally Heavy Hitter:
Playfield and Backbox sm (resized).jpg
Details at https://www.funwithpinball.com/resources/1947-bally-heavy-hitter

I can only speculate without a schematic. (If you have one, or the game manual, consider sending a good copy to IPDB.org). But looking at the schematic for '71 Action Baseball there may be a way:
Action Baseball Curve coil (resized).jpg
In this game the Curve Coil fires when a switch on the Mix Unit (in red) closes. The Mix Unit sounds like a step unit of some kind that determines when a curve ball is delivered. You could in theory modify the contact board so that the curve ball switch closes more often. It might be as easy as connecting a couple of the solder lugs together. It would take more investigation to know how this might be done. Also beware that in this game the Curve Coil runs at 120 volts so the game should be unplugged before poking around.

/Mark

Cool. I used one of those in my horse racing game but didn't know where it came from.
(details at https://www.funwithpinball.com/exhibits/games#HorseRace)

If you wanted the curve pitch to happen more often you could add another switch that would close at a different time than the existing curve ball switch. That would only require a heavy duty switch and an L-bracket to hold it in a new position. Or you could 3D print a new cam with an extra pin or two.