You might possibly want to taper the pleats into the small of the back - because the two measurements are not two circles vertically one over the other - there could be a 'bay window' effect at the front, from which the pleats would fall straight down from the waist, but there still be some inward curve to consider to the rear. Without it the waistband would crease up under the belt, or there would be a gap if the kilt was just buckled.

Try the effect with a towel and a few safety pins to see how something straight up and down would fit around you.

If, after you pin the towel at your waist kilt fashion, you can put your hand down a gap at the centre back, or pinch loose fabric at the sides then you will need to add shape to get a good fit.