My carb internals, all gaskets and brass pieces, are brand new.
Stock mains are 137.5, or at least that is what I pulled out of the bike originally. My replacement kit came with 132.5 mains, however. So, I am not actually sure.
Update:
I tried something radical; I lowered the main jet needle a notch (raised clip) and I lowered the main jet 3 sizes (down to 142.5) and she pulls much, much harder above 6,500 rpms.
The blasted dying at idle did not get any better. I tried lowering the float height 1 mm (26 mm to 27 mm) and it got even worse!
I have a theory though: I think the float needle is not opening far enough and therefore choking the engine as it waits for the bowls to fill. I intentionally adjusted the float needles in the past to only open a minimal amount; it's time to crank those puppies open a bit more.
Unfortunately there will be no more testing tonight; it's a weekday and my exhaust is quite loud...