hi I recieved a used transmission today from a salvage yard online. its out of a 1990 190e and my car is a 1989 mercedes 260e. anyways the transmissions do not match up my mechanic said it has electronics to it were mine does not. could the one they sent me be a 4 matic one?any help would be apreciated because the salvage yard is trying to say that its nit the wrong one and will not give me my money back.