flairball, wear them both if they make you comfortable. The braces will be prescribed to hold your kilt up (until you can have it modified) and the belt will be an acccessory. You would be best not to display them both. Hide the braces. I think you are referring to a waistcoat when you say a "tweed" -- yes? Tweed is actually a fabric and is used primarily in the making of jackets, waistcoats, greatcoats, trousers and, sometimes, kilts.