This is just my opinion, but that thing sounds like a total bucket. For all the money you'll spend just in parts, you might as well just shop for something that already runs. It might not be a real beauty, but you'll at least know what you're starting with. If the car overheated and the timing belt snapped (strange combination) either the overheat was SO bad that it destroyed everything, or the timing belt was coincidentally on it's very last legs at the same time.

While it sounds like a challenging project, I personally would not bother with it. It sounds like it's priced right, though. If you need body parts or a transmission or something, you could still make out on that deal.
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1992 940 wagon, low miles
as well as others.