Hello, I have a 1991 MB 300 SL Auto and I've just ordered a new door switch for it from MB costing £237.60. The current switch is not operating the forward and backward adjustment of the driver's seat. Is this an easy switch to replace? There's a tortoiseshell type facia covering the switch, but I do not want to break anything and I'm thinking it would be easier and safer for the MB garage to change it. Can anyone please advise me on the way to procede?