I have the chance to buy a beautiful 1975 300d with 128,000 miles for around 3500-4000 dollars...I've never owned a mercedes, but want a 300D or SD VERY much...I don't work on Cars...I want a good long-lastin car (I've had my convertible bug for 25 years) which is why I've zeroed in on a Mercedes Diesel...So is 1975 just Too old to deal with if the mileage is this low....I need advice please...........Thank You, Linda