Yup! Those are exactly the ones I pulled off in the above pic!
A little bit off topic, but-----I am also tearing down a 400 truck engine that has been sitting in the way in my garage for about 12 years. Are there any parts worth anything besides the block? It is a 1975 engine with 452 heads. Sorry, the exhaust manifolds were removed years ago.
Mine had the heads on it that are the same as the desireable earlier big block heads but with hardened seats. I forget the casting # but I pressure washed and wire brushed them and sold them on craigslist for $100 inside a couple weeks.
Cast crank = scrap, valvetrain=scrap (keep the rockers and pushrods), my water pump housing looks like a million bucks after a good cleaning and paint. Lots of good bolts and nuts to clean and wirebrush if you’re a cheapskate like me. My intake and valve covers haven’t sold at giveaway prices I will probably scrap them too but it never hurts to have a coffee can full of the little triangles. I cleaned up and painted the valley hold downs. Basically just the heads and any small parts ot unique hardware that are a pain in the neck and nickel and dime you to death when your budget is getting smaller at the end of a build.
Good luck