slant 6 running odd

allright i have been drivin this beast on and off after it was sitting for a some years, i have changed the fuel filter,rebuilt the carb and changed the cap and rotor. its still got a bit of a miss, and stutters when i accelerate sometimes. and when i stop fast sometimes it dies too. when it rains out it dies at stops and runs horrible. what do you think it could be. i am going to order some wires and get plugs thisweek. just wondering if anyone has had the same problem, maybe its something else. i have also run seafoam through it. oh its also hard to start after its been running a while and then sitting for a bit i have to hold down the gas usually. any help will be grealy appreciated and i hope this is the right forum to put it in. thanks !