Do you have to put the plastic bit at the bottom of the shock that the plastic sleave sits on onto the new shock? Can't get it off.

Don't really understand the question sorry. Front or Rear? a picture would help.

Front. The long black ribbed sleeve that gos over the piston inside the spring, on the standard one it sits on a plastic trim but this won't fit onto the new shock and it just hangs loose? Hope that explains it better. Not sure how to post pics yet lol