what so you think it is worth

Sounded like you were there looking at it with the owner. Either way, I'd go back, check it out thoroughly, then make a reasonable offer on it. If it's truly solid, it looks like a great project. Or driver, whichever. I'd love to find something like that. Actually, I did. My '72 sounds almost exactly like that except the outside paint was baked off from sitting in the sun (but fortunately, the interior was spared the same fate, oddly), but the rest is super nice. But the fact that this turns out to be a '70 is even better.