Thinking of buying a Street Demon Carb...

I have ran a 625 street demon on my truck for the last 4 years, it works great, starts easy cold 0 deg F, and will also start hot with no issues.
You do have to buy the mopar throttle arm and dissemble the carb to put it on.
I really like the polymer body, because it solved my vapor lock issues I was having with a 3310 holley.
Also the carb gives decent gas mileage, I got 14.6 mpg out of the last tank of fuel. Keep in mind this is good mpg for a 78 W150 4x4 with no overdrive.
Sorry I cannot answer your air-cleaner question, but I really don't see any issue with it clearing.