I have a similar motor to yours. A little bit bigger cam, 470ci and a Holley 850 street HP.

I had the same issues as you when I put it all together. I eventually had to go up to 50cc accelerator pumps diaphragms, a 37 pump squirter in the front and a 39 in the rear. Everyone told me that I shouldn't have that big of squirters in it but, that's what it liked and that's what it took to get it happy. After that, the fuel map was right everywhere.

I eventually put a better set of heads on it and the problem returned and I could not tune the stumble out of it with pump nozzles and cams. I sent the carb to a well know carb tuner and he too said that I should not have that big of squirters and that 30cc diaphragms and smaller squirters would suffice. When I got the carb back from him, it ran worst than it's ever run. I called him and began doing what I'd done before but, I eventually had to put the 50cc diaphragms back on it and bigger pump squirters. He did other emulsion work on the carb, which was the saving grace. I messed with the idle bleeds, high speed bleeds and a bunch of other stuff but, I still have not gotten the carb to do exactly what I want it to, it needs some more work. WOT is great, idle could be better but, my light cruise sucks.

Ultimately, what I'm trying to convey to you is don't be afraid to throw all types of pump shot at it. I don't care what people think should be on anyone's car. If you're running it on a dyno, with a wide-band or know how to read plugs really well and the AFR's are what they should be, than that's what the car wants. If than means 49 pump nozzles front and back and 50cc accelerator pumps, than so be it. I'm not saying it's right but, there is more than one way to skin a cat. If your fuel map looks awesome, then who cares what it took to get there. The car doesn't know the difference.