You are getting too much fuel at idle. (after making sure PV is good) Most common issue is primary throttle blades open too much exposing too much transfer slot. This will cause a rich smelly idle, idle mixture screws having no affect, and hesitation on acceleration. Should only be able to see about .020" of the slot below the blade. It should look square (ie only expose as much vertically as it is wide) Are you aware that the secondary plates can be adjusted as well? They should be open just like the primary. Adjustment screw only accessible from the bottom, on passenger side. adjust the secondaries just like the primary. put carb on and start the car. If it idles too high, you may have to take the carb off and adjust again, by closing the primary and secondary curb idle screws an equal amount. You may end up with no transfer slot visible. Once you have this adjusted correctly, your mixture screw should work. You definitely don't want too much transfer slot exposed. If that is the only way it will run, you will have to introduce more air at idle. Only way to do this is by drilling holes in the throttle blades. You should not have to do this though. You also should not need a squirter bigger than a 31. I would recommend you disable the secondary vacuum can on the secondaries until you have all your issues worked out, as that could be skewing your results. Once you get a good idle and smooth acceleration on the primaries alone. Then you can test different springs in the secondary vacuum can.