Karamoja, the 1900/1903 is narrower in the action when compared to the 1905/1908 and the 1910 is wider again. But as you are finishing the inletting and Camerons pattern is made for the 1903 you will have no problems. Just maybe ask him to leave a little extra material around the sides of the stock where the action sits. Also remember he has two patterns, one for pre-war and one for post-war.

Matt.