Just Bought a 65 Barracuda that sat for over 20yrs.

i'd yank the valve covers off and see how bad everything might be. should give you a pretty good picture of what the rest would look like. if that passed the sniff test, i'd pull the plugs and squirt some MMO in the cyls and bar the motor over by hand real easy. make sure it's not clunky and chunky or super stiff in any one place.

throw some gaskets at the carb, do the absolute cheapest points, condenser, cap, rotor wires & plugs i could get. drain it and throw some cheap oil in and filter on. then see if could get it to pop and fart on a nurse bottle.

if it makes fire, then i'd sit down a make a plan of attack. deciding what i wanted to upgrade, what absolutely needed to be replaced and what direction i wanted to take the car.

considerations such as: why rebuild the brakes if upgrading to discs or bothering to repair [blank] when you're upgrading or replacing it are key to not spending the time and money doing something twice.

make it safe, make it reliable, upgrade smartly. sounds like a fun project!