The 261 cam is a good choice but so are some custom grinds. I like my 3/4 race from Patrick. I'd do the 375 CFM Holley if doing it over however. The twins have a greater "wow" factor but harder to tune and forget those electric chokes. I'd mill the head .040/.060 and replace the seats. As for the pistons, guides, etc it will depend on what you find inside. These are expensive engine to rebuild so why replace or upgrade what doesn't need it?
Good luck.
