Replacing the clutch plates isn't really any different from any other wet multiplate set up.

Things to be aware of on XT660s are:

There are three slightly different types of friction plate indicated by notches on the tabs) and they must be fitted in the correct order. There is only one 'type 3' plate and that's easy to identify as it's got a large internal diameter - this goes in first. The 'type 1' and 'type 2' friction plates are then alternated between the steel plates starting with 1 then 2 etc.

Make sure the teeth on the pull rod are facing rearwards and be very careful that the engage properly with those on the shaft. It is quite common for the teeth to get mashed up if not engaged.

Before connecting the cable, make sure (when the operating arm is pushed as far forward as it will go) that the punch mark on it and the casing line up. If they don't you'll have to take the lever off and move it round a few splines.

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