Hi Dave, I have just seen your reply, if you are able jack the front up, you need to do this by the jacking point under the N/S, I place a piece of wood on the jack top when I do it to spread the load, with the wheels off the ground hold the wheel at 12>>>>6 and move outward, is there play? check the tyre tread, have you picked up a bolt in the tyre. the Mech for the car is a combination of bars on the N/S >>Off/ S, try & see if there's play in them, myself I doubt it will be this as it would affect the workings of the Roof itself, did he check the Torsion bar? these cars are prone to rubber wear, they are not that bad to do & not expensive, you may find what I'm about to say stupid but here goes, is there something loose under the passenger seat like a tin that's rolling about? the reason I say this, a friend of mine years ago could hear something knocking coming from the N/S it turned out to be a tin of peas under the seat ( True Tale) Has the back seat been lifted fir any reason? these can be a sod if not put back correctly.