You
can also swap on a Rochester Quadrajet - the other spreadbore. Keep the
economy (relatively speaking) of the little primaries, and the punch of those
huge secondaries. This will require very little in the way of
adaptation. Throttle cable linkage may require some fabricating, but
nothing major. A benefit is that the Q-jet is so common, and used on such
a wide range of vehicles, that you should be able to get a good rebuilt one for
a decent price.