I presume this is for a street car, with a radiator and radiator fan that draws air through the radiator and discharges into the engine bay. (typical street car setup). What's the airflow (in cfm) of your fan? I'll bet it far exceeds that required by your carb. So it won't be starved for air. Design the scoop any way you want, the one in that pic looks awesome!
If you're going to duct the scoop directly to the carb, take the carb opening size (measure the arae of your throats - in square inches) and multiply that times two. Your scoop's inlet opening size and duct/tunnel leading to the carb(measured in square inches) should be no less than twice the square inches of the total carb throat area.
Hope this helps.