On a hunch I tried this over the weekend. Shimano never changes anything drastically, even when they redesign parts. When I heard the Saint derial was designed for a 10 mm axle, smart bet was they were using the same 10mm x 1 thd every Shimano rear hub axle runs. To do this you will need a longer 10mm x 1 axle, hollow or solid; your choice - Wheels Manufacturing makes several different ones, and you need 1 axle nut for the non drive side.
I'll take a pic at lunch time and post.
I'll take a pic at lunch time and post.