^^ Great idea with the felt^^

Thanks.  

This is what I mean for folding over the felt to the underside. I didn't trim these felt strips any narrower at all just folded them over to the underside of the playfield.
I currently have "chrome" mirror blades on the CV and with the attachment tape and the felt strips it is a moderately snug fit. The important part is that the felt strips will now not snag or catch on the sides of the cabinet/mirror blades, plus do their job in acting as a cushioning buffer and are flexible enough that the playfield still slides in with ease and without scratching the blades at all. So you can just raise and lower the playfield in the usual way without worry.