Perhaps the important question is: how do you intend to wear it? If you will wear it like a traditional kilt then the measurements you have take are correct and you will make the waist measurement 50 inches to accommodate your "prosperity". Some folks, however, prefer to wear contemporary kilts lower on the hip, like jeans. In which case, you will have to take a new set of measurements; and perhaps also make the front of the kilt a little shorter, to allow for the kilt to fit underneath your "prosperity".

Our gracious host, Steve Ashton, has put together a great video explaining the measuring of both styles of wear, and their advantages. IT can be found here: http://www.xmarksthescot.com/forum/f...t-video-26096/

Best of luck! I remember making my first x-kilt. It is the gateway drug to what many on this forum consider our addiction. :-)