Quoted from slgerber:

This is what I used:
https://ksarcade.net/rottendog-7-digit-led-display-system-dis079.html

Quoted from SkyKing2301:

It's not as fancy as you're making it sound, lol. Above the pop bumpers, there are the three rollover lanes, labeled U, S, and A. When the ball rolls through a lane, its corresponding letter lights up. When you light all three, the bonus multiplier increases and the U/S/A lights turn off again (so you can try to repeat the process). The "lane change" we're describing is simply changing which lane is lit (if you've already lit one or two of them). For example, if the ball rolls down the U lane, U lights up. Then maybe the pop bumper hits the ball back up the S lane, so S lights up. (Now U and S are lit.) Then maybe it looks like the ball will come back down the S lane again -- but it's already lit, so by hitting the right flipper button, you "move" the lights around so now U and A are lit instead, so when the ball rolls down the S lane, it completes the set of three lights and the bonus multiplier increases.
Simply put: you're just using the flipper button to change which rollover lane(s) are lit and which are not.

Quoted from privation:

Thanks.....local pinhead has a rom burner, set me up with a set that I'm picking up tomorrow at cactus jacks fall face off in okc! Will post pics up as I start putting this back together