Finally got the build running and partially driveable but I'm in a pickle on getting a fan or fans. Due to lack of room under the hood with the cummins in the Chevy I'm looking into fans. From what I read the factory mechanical fan will move 8500 cfm. I'm really interested in dual 15s but only moves 5500. Will this be sufficent enough for towing 10k+ in dead summer in southeast tx? Or will I be wasting time and bowling water? Any suggestions?