[Toivo]

others may know more about this, but as far as I know, the only difference between a Boss block and a normal 302 block from the same year are the screw-in freeze plugs and 4 bolt mains.

Is this JUST a block, or does it include a crank as well?

Unless you're looking for a numbers-matching piece I wouldn't value it any more than a regular block. Even the 4 bolt mains aren't all that important; at least not to me. I think that unless they're splayed anyway, they actually weaken the bottom end, you'd be better off with 2 bolt mains and a girdle.

Just my opinions. I know some people place a lot of value on being able to say things like "it's a Boss block" with "4 bolt mains" yadda yadda yadda. At the end of the day, it's just another block that's seen better days.

again, JMO