what so you think it is worth

Exactly what abodyjoe said. Another thing that usually works in situations like this is to say that you want to bring it back to great condition and really take care of it, and that it would be appreciated. All that is true, and when someone has that sort of family attachment to a car, but it's really not something they need either, that is often enough to get them to take the last step to selling it.

The wife wanting him to get rid of it is definitely motivation though. And if a 70 is sitting out in the driveway, it's only a matter of time before others notice it and/or word gets around about it. Oh, and the fact that you've posted it up here with the general location. Good chance it'll be gone by spring. Cash in your pocket with a decent offer, and get it into your driveway ASAP.