.

The post cap rubber fits right over the tooth of the habitrail. I tried installing two to make it symmetrical, but this caused it to miss alot. I picked the rear one next, and it has been working almost perfectly now.

I should mention I tried many other things, and this was the only thing that worked for me!

I got the pst cap rubber from Terry at Pinballlife.

http://www.pinballlife.com/page110.html

Have fun!