For all you folks with the ford rearend. How full is full as far as how much lube to put in? Motortrike manual says 3.3 pts,and also says to within 1/4 to 3/8 inch of fill hole??? 3.3 pts doesn't come close to the fill hole. Acually 2 qts doesn't come close to the fill hole. So what is the right answer?