The car in question is a 250C, isn't it? Imagine the cost of putting your car in good order vs. the cost of finding a 250/280C in good condition. Unless I'm mistaken, you can find a good one for four figures, or approximately the cost of rechroming the rear bumper on your car. Throw the old girl a retirement party. If you manage to get it running without replacing those rotten fuel lines you could even have a barbecue!