I agree with Sweet. Check the vacuum leaks, most likely a missing hose or the wipers not hooked up. Some may not agree on my method of checking for vacuum leaks, I use starting fluid on a
cold engine. I spray around the carburetor and all vacuum lines. If the engine revs up, you've found the first leak. Look for open ports on the intake manifold and carburetor too. Lot's of time, it's the hoses to the wipers, they get rotted and are not replaced as they should be. You can experiment by placing a flat piece of cardboard over the carburetor and slowly cover it, if it starts running better, you have a vacuum leak. The other way is to get a vacuum tester, either way works.
Dirty or corroded points will cause it to idle rough too. Replace them or clean them and check the gap. They should gap at about .018-.022 or the size of a matchbook cover.
setting points and timing Setting the idle Make sure you check any inline gas filters too.
