edelbrock 1405 problems

That's above my pay grade, but I get this part;

But light stumble to WOT.

My question is what are the circumstances surrounding this stumble?
And what is the rest of your combo?
Such as car weight, rear gears, TC stall, and in what transmission.
Then;
at what rpm is this starting from?
and in what gear?
And from what throttle position?
And what is the power-timing during the stumble?
and I suppose it would help to know how soon after the carb goes WOT does the stumble occur, or is it during, or before?
For the most part;
a light stumble is a momentary loss of airspeed or fuel.
As always; first things first; make sure the float level is correct and that the bowl-vent is clear.
If the pumpshot is all used up when the stumble occurs, you might have to pop the M-rods up sooner,faster.
When all else fails remove the rear boosters and prove the rear fuel circuit is open.