When installing flaptrack 3 or 6, the AMM (27-51-27) states that you first install and tighten the fwd 3 bolts and then the aft 3 bolts. But then it is often impossible to install the aft bolts, especially the middle one with the torque washer. It even happens that you cannot get the required torque on the aft bolts, and the torque washer will keep turning even with the maximum torque applied.So this tip is to install the aft bolts first and torque them. Then try to install the fwd bolts and torque them. It can save you a lot of time. See pictures below for the location of the bolts.