Cheers have read/ heard that before but wasn't sure how necessary they are
took the wheel off this morning and removed the caliper and carrier then cut the cover inhalf with a pair of heavy duty tinsnips and removed it ,it had rusted away round all 3 mounting bolts ,couldn't be bothered to remove the disc and rebolt the cover back on with some big washers, when I get the time ill probably remove the other front one awell .