[Zman]

Hey Marlin,
Sorry to butt in....
There's been a lot of discussion regarding Holleys on the "other" site lately. THE largest contributer to an off idle stumble is the Power valve. There are a couple different recomendations, but I have found that if you start with a power valve rated about 1/2 of the manifold vacuum, you'll be pretty close. In your case, you have around 20" of manifold vacuum, so I'd try a 10.5 primary power valve. You may have to experiment a bit to find out which one works best, but they're cheap, and simple to change. I would NOT recomend blocking off the power valve for a street driven car.
Ignition man on Steve's site is an X Holley employee, and 64pronova seems to know his stuff, and has helped several guys get their holleys dialed in.
I just went through this same thing when I changed engines in my 69 nova. I have a pretty radical solid cam (548 lift adv. 304* 264*@.50 duration with 108* seperation) and I have only 7-8" of manifold vacuum. The new Holley double pump I just installed (on a Victor jr intake) comes stock with a 6.5 power valve. In my case, the power valve was pretty much open all the time, creating a rich condition at idle, and poor throttle response. I changed to a 3.5 power valve, and the idle cleaned up, and the throttle response improved dramaticly. I may experiment with shooter size, and acc. pump cams, but just the power valve alone made a big difference.
In your case, I'd guess the power valve is too low, and not opening soon enough. I think you're just masking the real problem by changing shooters, and acc. cams. The main jets will have little or nothing to do with the off idle condition. I would suggest that you put everything back to stock, and start with the correct power valve. THEN experiment with shooters, and pump cams until you're happy with the performance. I'd be willing to bet that with the correct power valve, you won't have to tweek it much to get the desired performance.
Hope this helps,
Dennis