Before you start altering permanently.
Remember that when coins are employed as part of the game they carry with them all the grease, dirt and fluff they gather from every pocket and purse they've been in. That gets transferred to the next place they end up in.
If this was my machine, I'd remove the playfield from the case, get all of the coins off the playfield and feel the smoothness or lack of in the trips when they move. I bet when you look at the playfield without coins you'll still see all of the outlines of them. That's the dirt, and it's slowing and grabbing the coins.
remove it all, and when dry polish it with a furniture spray. Clean the inside of the glass as well.
We'll all now await your next post, which you should title, "How do I get a Bell Cascade back together without the trips all falling off?"
Someone then will reply and tell you about laying two chairs face to face with you lying on the floor between them and reaching up.
ps when you clean the glass on the inside, remember it's the side with the transfer on, we can get replacement trips, but I've never seen replacement transfers.