Quoted from wxforecaster:
Proposed Solution. Two digital levels should be installed under the playfield (front and back) that report back to the display.
No need for "two digital levels". A single 3-axis accelerometer will do the trick. As Zitt mentioned above, we've implemented digital level GUI elements into our P3 machine. They get their data from the accelerometer on the P3-ROC controller board, which is mounted under the playfield. Also, the machine is designed for all of the legs/feet to be at the same length for 6.5-degree playfield pitch.
We're happy to work with other manufacturers to help them implement digital leveling and force-based features into their games.