Thanks mate,i've done it. Following advice on the S3 forum....i warmed the engine first,as it softens the rubber mounts(slightly!!),then it's a firm tug on the right rear,then front right,(both pulling up) followed by pulling up and towards the front with the front left,being careful not to grip the front,as the plastic is weaker -use both hands at the side, and finally the rear left comes free much easier.
Thanks in particular to JohnnyC.