For the weight and balance, they have you make a series of measurements for the distances to each of the wheels from the datum (which is 70 inches forward of the leading edge). I'm wondering why this is necessary... with the pre-punched kits, should these values differ in any appreciable way from Vans' numbers (i.e. the numbers given in their "Sample Weight and Balance")? They give 34.5 inches to the nosewheel and 91.88 inches to the mains. I jsut wonder if the difference due to builder variances would likely be smaller than the error with which I could physically make the measurements...