Hi all......just a quick update, the new plugs have been fitted and I'm really pleased to report no more pinking, car feels great 2 plugs did feel not as tight when undoing so may have contributed to it, and the rear clicking axles ( both sides) have had the treatment with Lucas Extra Heavy Duty Grease and I'm happy to say the clicks "HAVE GONE""...................on a down note, some **** has dented my door in the car park at work.......so annoying as she was perfect.....so a call to the dent removal guys is on it's way,I just can't stand dents in my Z...........ather than that. HAPPY DAYS.