Quoted from fredsmythson:The original black foam was made in the devil's workshop and boxes of this evil foam were sent to the Gottlieb factory... This black foam will eventually destroy the paint on a backglass... I always try to get rid of the black foam that touches the middle of the backglass, and then use the Velcro technique on the edges of the backglass... I thought the Gottlieb design of holding the backglass in place with the light board was a weird one...
I can attest to this. The rattle pad messed up what was otherwise a pretty pristine backglass in my JO. I got a new one from Ron Webb due to that.
Remove, use the fuzzy side of velcro as Ken suggested.