As long as they are aligning the front and rear sprockets, and assuming stock sized parts for the carrier and axle, there are only one reason the guide would have to be moved outward 1/2": If that left tube coming from the pivot point was moved right 1/2" at the point where the guide is, and only in relation to the rear carrier tube.
So, I guess the best measurement would be, rear carrier tube edge(part that clamps the carrier) to outside edge of guide mount. If that number is different on TheSmith's bike, then the swingarm wouldn't work with the rest of his parts either.