Here we go, big -4 vs. -6 conversion.
mr-dwight, see what I mean?
It's obvious your wallet isn't as willing as your desires. If it were me, I would find a decent 2.0L (sidelined from one of the above-mentioned "-6 conversions"), tweek it with a few performance mods (cam, pistons, minor headwork, carbs), and drop THAT into your '70. This way, your car isn't sidelined for weeks/months/years while you figure out the cheapest way to install/route/solve this-or-that problem.
Don't get into this argurment, unless you have the $6K+ entrance fee.