Glen, I think you asked too many questions in one single post.
That said, if none of the real engine builders give you a detailed response, then I'll tell you the story of my 428 build, that started out life as an externally balanced engine with a goofy flywheel from the Ford factory, many, many, years ago. Then, almost 50 years later, a stork would drop my new bundle of joy on the doorstep and it was now an internally balanced FE of 447 cubes. The harmonic balancer, unfortunately, stayed the same (maybe that's why it spun apart). Hopefully blykins, barry, or keith will give you an experts post and you won't have to rely on an enthusiastic hobbyist and his story (that has absolutely nothing to do with a small block anyway).
