Thanks... I've already got quite a few hours in it, taking the primary bowl & block off, drilling little brass setscrews, reinstall, drive, repeat...
It runs great, but also rich to pig-rich until I started tuning. If I didn't have an AFR gauge I'd be happy with the driveability (if not the mileage) :p Anyway it's basic physics. This larger carb only needs a tiny throttle opening to cruise, which is on the t-slots. It will always be richer than the old 4780-2 I converted to 4-corner and adjustable brass.