I thought this was a good idea, so I did the same thing. I haven't played it yet with the felt, so I'm waiting to see how it works. I'm not exactly sure how The Dude did it, but for the metal shooter I cut some felt strips from a sheet I got from Joann Fabrics. It had an adhesive backing, so just peel and apply.
Also, I cut out some v-shaped mylar and put it on both of the inlanes where the ball drops. And per Centerflank, I put v-shaped mylar on the shooter lane . . . I'll put Cliffy's as well, but am waiting on those.
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