Quoted from MJW:
I have heard prem and LE may have got more clear but kinda doubt it. Check out the pic. This is what your protector will prevent. This is a home use game with not a large amount of plays. Your dumpster looks like you are somewhere in Europe. Just curious.
I just don't know how that happens with a low play game because I rarely ever get the ball in the bell scoop. Maybe it was a 1 shot, 1 chip fluke? I added bell and jukebox protectors to mine though. The bell protector was a time consuming to install.
As for the Z connectors under the playfield. Some are marked, but not all (on my game).