Ok, you've just been told (for example) to take the left wheel out of roomba but have no idea how to do it look no further.
To get to roombas innerds (take the covor off so you can see the workings) go here.
Now go to the page that refers to the part that you want to replace/remove
(if you are thinking chm for your disco you are incorrect the chm's are only on the 500's the 400's/disco's have brush decks)
must be read