I had the same thing going on. It would buck once or twice and die. Also, sometimes when I stopped short, the engine just killed.
I put a new (rebuilt) Pony Carburetor Autolite 1100 on it. The idle was high out of the box, but the choke pulloff worked right and everything. I fooled with the timing and leaned out the air mix. It started revving real high, so I backed the idle off to 700 RPM in neutral then put it in drive. Boom, dead. So I backed out the fuel/air mix some and ran the idle up to 800 or so and it works fine now. EXCEPT now the choke doesn't close automatically and opens right up when I crank it if I close the flap manually. The car starts hard but runs fine once it is warm.
I'd say raise the idle a tad.