[drolston]

First, the small hot rod air cleaner (if the filter element is clean) does not choke the engine until the rpm is way up. It is not going to cause the engine to run rich for normal driving.

Second, did the lurching (intermittent momentary total engine not firing) go away with the new condenser and plugs? If so, great - that makes trouble shooting the remaining problem much simpler.

If the only remaining problem the exhaust popping, something is causing some unburned fuel/air to enter the exhaust stream. Main jets too large can cause that to happen, and it will be most pronounced when decelerating in second gear. Since you get popping at idle when the idle circuits determine the mixture, not the main jets, I would rule out the main jets for now.

Having hopefully fixed the ignition problem, maybe you need to adjust the idle jets. Close one until you hear the rpm drop a little, then open it back about a quarter turn. Then do the other. Reset the throttle idle adjust screw to get a nice idle (about 600 rpm or a little less), then do the idle jet adjustments again.

If you are still getting exhaust popping at idle, run some MMO through the carb while jazzing the throttle. If that does not fix it, run a compression test on all cylinders and report back.