ML383! I think that is a 383 out of a 1959 car. That block might be worth some money to someone who needs it. Might only be one guy in the world who needs a 1959 383 block but if you can find him I'm sure he'll be happy to find his block.
The 1968 engine will be worth more money to most people. That could be a RoadRunner engine with those HP manifolds.
The 1968 engine should have a casting date on the side and it might have a VIN stamp above the oil pan rail. You can also check over the '59 engine for casting numbers and dates. I'm not sure what they used back then, I don't think I've ever seen a 50's casting. Those are very rare. If that block can be saved I'm sure you'll find someone who wants/needs it.
