Bummer you had to go through all the trouble with your engine/s. There are several things that come to mind assuming your engine and carburetor are in good shape as you stated. To me, your idling problem sounds like a fuel, vacuum or distributor issue. I would investigate and make sure your gas filter in the tank is clear and check your fuel pump for leaks and performance. Blow out your fuel lines since it's been sitting that long. I would also disconnect the choke to troubleshoot the problem. Get yourself a vacuum gage and hook up onto manifold port to see how much vacuum its pulling (should be between 15-20 roughly) at idle. You can tune your carb with the gauge installed to get the highest vacuum and steadiest needle. Try this and report back. Good luck, have a few beers with it to calm the situation LOL....