Bill The 1919 ship date listed for your Grade 0E frame is incorrect, as the Grade OE was last produced in 1912. There are differences between the barrel flats of early R framed Smith guns when compared to later production barrels; and another thing to consider is that the OE ejector fore iron won't be compatible with the extractor barrel set, so hopefully you also have the complete matching forend from the later R framed barrel set. Photos of the OE frame and barrel flats from both the OE and extractors barrels would certainly aide in giving you direction.