[antonye]

Now you know that the clutch stack height is ok, you can work through the system.

Give the plates a good clean with brake cleaner and then reassemble.

It may be worth bleeding through the clutch fluid and even changing it if it hasn't been done for a while; usually it will be done every 2 years as part of the major service.

Give it a really good bleed to ensure you get all the air (and old fluid if you're changing) out of the system and then reset the span adjusters and try again.