if one will study the tuning booklet supplied with the edelbrock carbs they will notice that a "step" in metering is 4%. what i have done is use the percentage of change to dictate a step and not orifice sizes. i put together a cheat sheet that gives the square inches of area for all jet and metering rod sizes/steps. i figure everything on percentage of change using both jet area and rod step area. never do i grab a jet or rod out of the box and just figure i'm changing "one step".

as far as the pump nozzles go you can make them anything you want with small pin drills.

to my knowledge there were two types of floats made for afb's, small and large. none of the edelbrocks have the large but some OEM carbs did, like a 440 avs. i don't think the smaller float gives as good of fuel control as the larger. i have found that for what i do the smaller needle and seats seem to perform and drive better and i think that's due to poorer control with the smaller float.