Roomba pro elite change drive wheels

Question

How do I change the drive wheels on a Roomba Pro Elite.

I need a manual on how to take out the drive wheel(S) and replacing them so it will work.

One of the drive wheels has lost the rubber tread. I have to complete drive wheels but no other instructions on how to replace them. I have all the s***w out but there is some thing still holding the unit together so I can not get at the drive wheels.

Please help.

Clayton Knapp
[e-mail]