What Carb for Poly Stroker

Well I pulled the 600 off to measure the diameter of the adapter holes, they were about 1 5/8". I noticed some of the cork gasket was encroaching on the hole so I pulled the plate off, tidied up the gasket and then took my dremel to the plate bores. I didn't go crazy but they were measuring 1 11/16" after I'd finished which was a slight improvement. The adapter plate bores now have a slightly coarse finish which might help with fuel atomization for that extra 0.1hp!
While the carb was off I thought I'd try the 700 DP again. It was running ok before except the off the line bog. I had it on my work desk and set the Transfer slot on the primaries to have the "square" or a slight piece of the slot showing. I'd read the secondaries should be showing the same so adjusted them too.
Put the carb on and it fired right up but was idling at about 1,000rpm even with the idle screw all the way out. Must be from me adjusting the secondaries (I'm running MVA)? I gave up at this point as I'm flat out in work and there's a big cruise this Saturday for a charity for Christmas so I need the car running good. Adjusting the T-slot with the carb inverted is fine when it's come from dry storage but to pull it off, drain it and still probably have fuel going everywhere didn't sound like fun so I just whacked the 600 back on there and took it for a spin.
Geez it runs good with that basic Holley on there, even on a 95° day like today. Geoff if you're ever in Queensland give me bell and I'll show you how good a car can run with a "leave-it-in-the box" piece of crap Holley. Then I would be grateful if you could show me how to tune a carb properly because I really don't know what I'm doing. I'll supply the beer.
After all the advice you guys have given I'm now tossing up between the AVS2 650 and a new Holley, either a 750 Vac Sec or perhaps a 650 DP?
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