The 6.5 puller moves air at ≈330 cfm; the 7.5 rate is ≈440 cfm. What many riders have done is install
a fan switch to run the fan when they think it's needed. It should not be run all the time. With or without the override switch, the 6.5 has gotten high marks around here and using it could lessen anxiety about fitment. Some have installed
fuel coolers because hot fuel within the tank radiates excess heat onto the legs; likewise,
insulating the fuel rail and the fuel return line also have been done. Insulation beneath the tank has also been improved, including deploying the legendary johnny blanket.
The guide below has a few other suggestions. Some involve both BMW and aftermarket parts that are no longer found as new stock.