1975 Ford F-150 quit running

Engine Mechanical problem
1975 Ford F150 V8 Two Wheel Drive Automatic 120K miles

Hello - have been driving my '75 F-150 (360 cu. In. V8) for about a year. Recently began "coughing" and "sputtering" while on the interstate or at high-speeds (not necessarily at high-rpms, but definitely while trying to reach freeway speeds). Was thinking, "hmm, better get that checked out, " then one day (while on the interstate coughing and sputtering) the engine died and wouldn't restart. I Replaced the fuel pump (seemed like a good candidate) but still won't start. Engine turns over and will run (briefly) if I "prime" the carburetor with a small amount of gas. Pulled the fuel line going into the carb and turned the engine and saw gas coming out of the fuel line, so I'm thinking the new fuel pump is working. Is this a carb/choke issue? Or something else. -Thanks in advance!