Points seem like the easiest to change so far without rewriting sections of the Williams custom based language script of assembly game logic.
Chip locations:
>IC14 : Game Rom 1 : E000 - E7FF
>IC26 : Game Rom 2 : D800 - DFFF
Main goal was to make a tournament ready version with fixed mystery score (completed) and to eject the locked balls at the end of each player. Also wouldn't mind trying to fix a few bugs I've seen so far (L-4).
1. after all of the upper playfields left bank of drop down targets have been hit, during the second or two before it resets, if a ball goes down the left inside lane, you will receive 10,000 points.
2. after all of the lower playfields left bank of drop down targets have been hit, the ball could end up staying in the lower playfield multi-pall eject hole a few seconds longer than normal.
Believe I saw an all-in-one device that was to merge all of these together, don't know about the current status, last I checked, believe they were trying to get licensing rights from PPS for the software. I'm dabbling on my own, less intuitive design that uses the unused 40pin expansion port on the CPU board, and remade the magna-save relay boards, and a very low to-do on maybe home make a new transformer for it.
That's about it for now, it's a slow process since it's all done in spare time.