NHRA Superstock engine rules

Can anyone give me the basics as far as overbore/stroked cranks allowed?

What about intake manifold mods? If aftermarket manifold are legal, are home built or low production manifolds legal?

Throttle body size and placement change restrictions?

Can the frame be replaced with a full or partial tube frame on a car that's orginally a full square tube frame?

How far from OEM can you go in these areas? (SS/E)