To me it sounds as though there may be junk in your gas tank. Do you notice the carb's gas filters? Anything there?
Next guess would be to check for vacuum leaks. You have a 73, so there is no EGR smog crap, but still a leak could be around your carb or intake manifold.
Did you replace cap/rotor of distributor when replacing plug wires?
I would throw an HEI distributor in it. It is very simple to do and won't require any points. YOu can remove your external coil as well.
Check your coil now that i mention it. They are cheap, I'd replace it since you don't know when it was replaced last, that is, if you choose not to go w/ HEI distributor.
SgtDel
aka "Andy"
www.delbridge.net
1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4