I've only used Weber 40 and 45 DCOE side drafts on 4 bangers. Beautiful tunability, and the 48's should give you more than enough breathing with the right sized chokes. Takes lot of parts to really tune them unless you can find a similar setup documented so be ready to spend some $$ on jets and emulsion tubes and chokes. Spend the $$ to buy a very good throttle linkage; sync'ing the 2 carbs can be a constant pain if you use cheap linkages. That is an advantage in the standard 4 BBL carb, but one that can be overcome.
Just IMHO on the Voodoo cam: be careful on the RPM ratings of most cam makers; they tend to be optimistic, especially on the low end of the RPM range. Lunati is no real exception here; the real torque badn will start maybe 500 RPM above the lower advertised limit. Crane is the one company whose catalog RPM range numbers tend to be fairly realistic. So if you really need 1800 RPM as the low end, then I'd look some more, but if you can use it with your gearing, 2500-6200 RPM is a pretty good usable torque band for racing. As said, a wide torque band is important in your use, especially to set the weight transfer to the rear when coming out of corners of all different gears and radii.
If you knew the road courses you would be running, and the gears and RPM's our of the corners (or the exit speeds so you could figure the gears and RPM's), then that sure would be helpful to your decision making. As I suspect you know, the 1st gear in that trans won't be of much use, but at least your steps 3-5 aren't too awful.
