Could someone please tell me if the camshaft sprockets can remain installed when removing cams from the cylinder head on a 2010 S40? There is a pulse ring for the VVT pickup (i think) on the drivers side end of both cams also. Can they too remain on the cam for removal? I have read through every post on every volvo forum and watched every youtube video I could find regarding this and in all cases the camshaft sprockets were removed. Thank you for any help you could offer.