My nephew is driving a 55 Hudson Wasp everyday and is getting tired of the little flathead on the hills around his home. So yep, you guessed it, he has a little 364 Nailhead he is building for it. It will look stock but have a nailhead in it.
Our dad was a Buick salesmen when we were growing up and my brother really jumped into it with both feet. He is reproducing (having them made) a 671 blower manifold and 6x2's along with a bunch of other things like alternator mounts and stuff like that. He is really doing well with the nailhead stuff.