340 fuel/ignition issue?

Thanks for checking in, Bewy!
I think secondary operation will be OK now, but two issues:
1) It doesn't want to drop the last little bit down to proper idle. Will close down seemingly smoothly, but it hangs up, so motor races a bit. Returns just fine with pump linkage removed. Maybe just more than the double springs I have now, or stronger ones.

2) As I've said earlier, when first installed it metered beautifully. Then going into secondaries at WOT it apparently really flooded out. There may have been an issue with secondaries, but they seem to operate properly now. The flooding appears to be elsewhere.
After I've pulled it apart, cleaned and double checked everything and made no changes to rods/jets, yesterday it was giving me 11.5 A/F (instead of previous 14.5) at warmed idle, still smelling rich, sooty plugs ...and the idle screws were making little difference.

I can't locate what's causing this. Bewy, you mentioned checking the base gasket but it's the same one I used when things were working well. (The thick factory style.) I did find the tiny hole under secondary blade clogged, but cleared that.