Carb Question - 2BBl or 4BBl

[Ironhorse]

I have the chance to pick up a Q-jet carb for little of nothing. Elec. choke and needs re-build. My truck currently has a Rochester 2BBl with stock cast iron intake. Truck is a stock 350 4x4 with 4 speed and stump puller gearing. Needs all the help in can get mileage wise. TBI is not an option so question is:

Considering all the angles, such as miles per gallon, pulling power, driveability, ease of maintenace, etc: Which would you use, the Q-jet or the current 2 bbl carb. Also have a early 80's Camaro Z-28 GM aluminum Q-jet intake so the intake question is already taken care of.

On a good day the truck gets around 11.5 mpg. at about steady 55 mph. Would I see much improvement with the 4BBl Q-jet? Have had several guys at work tell me it will do better than the 2BBl if I leave the foot out of the back two butterflies.