Harry, what I've read from a reliable source (Remington Society of America) all P14's made in December 1916 and after were built with the larger bolt lug upgrade. It has been my understanding that the Weedon process was established to upgrade the surviving stock of pre December 1916 built rifles to the Mk I* standard. It is also my understanding that not all of this work was done at Weedon itself but was contracted to several small shops that were capable of this type of work. If you know what to look for and the key to the codes (which I don't know) you can look at a Weedon process rifle and know where the work was done.

Thank you for the name H. Morris & Co. Deep in the gray matter I had some recall that the firm was Scottish but just couldn't draw out the name. Hopefully I may remember this going forward but my hopes for that aren't very high. - Bill