That's another set of instructions I won't need to write... C'est la vie.    There are enigneering drawings for the LMS D2093 version in Official drawings of LMS wagons No.1 by Wild Swan. The panel spacing is the same on these and the BR ones, which as far as I can tell are the same as the LMS ones except for changes in the brakegear. As has been suggested the GWR ones were different and by the look sof it the LNER ones as well.   The wheelbase for these was 9' (apart from the final batch