Slant 6 dies.

Worth a try:

Pull the air cleaner off, rev the motor up to about 2k RPM. Then open the throttle all the way, and use your hand to choke out the carburetor and stall the engine (still holding the throttle wide open until it dies).
This will flood the engine, but just put the pedal to the floor when you crank it back up to clear out the excess gas.

What this does, is, if theres any small crud thats gunking up the internal works of the carburetor, the few moments of intense vacuum (wide open throttle but closed off to air) will suck the junk out the vents/venturis/jets. This has helped me with a few rough carbs in the past, and, may take a couple of tries.