RE: TOM BRETT'S DESIGNS-UPDATE
Reminds me of the Taurus plans issue. You have to face several sources of "errors" or differences. A good reference is always the rib spacing being a nice round number. And nearly always the tip block roundings are not drwan exactly to a specified wingspan. On the other hand, nobody would specify such odd wingspan like 60-3/4 in a title block.
Besides, to me it seems the DMECO plan has shorter wing span and fuseleage length. Consider that it (as well as the original plan) might have shrunk after being exposed to humidity, glue and whatever. Shrinkage may be different in horizontal and vertical direction. Especially kit plans need not be exact as long as the parts are cut precisely.