You found that the .020's are way too lean if you could not keep it idling. Good test.
There is not much difference between the .030's and the .031's. I would say just pick one.
I think you found that it idled fairly well on .065 IAB's. If so, then I would go with that.
Lets say that you test the .030 IFR's and the .065 IAB's. If this idles well, then start with changing the HSAB's. Get it idling again first at your normal idle rpm, then move on to leaning out the HSAB's.h
Lets say that the .028 HSAB's are too rich which are bringing on your mains too soon. This may be what is causing the rich condition (as long as the plug wires are good, there are no vacuum or intake leaks). I would make a guess at low to mid 30's on the HSAB's for your test.
You just need to keep testing!

Note: My .033 HSAB's bring my mains in right around the 2500-2700rpm range. Remember that the main jets and the MAB's are a team and they work together. One could be fine while the other could be off. I would suggest leave the 64's in there and lean out the .028's.