Recently sourced all the bits for this as i was told it was possible .
 Well it is, but you need to make up and fit a new stem for the bottom yoke as there is'nt a suitable taper bearing to suit the 851/888 headstock 916/748 stem. 
 I toyed with the idea of making up some  cups to suit the 851 headstock but unfortunately the 916 stem is also to long and I figured making up a spacer to sit under the stem nut  would have looked naff 
 
   I may make up a new stem for the bottom yoke and make the sod,s fit but then theres also the ignition switch mounting,lockstops sorting and speedo drive/frontwheel to think about .  
 In all honesty I might be better off getting the M1R,s rebuilt (topping out atm) or finding some early 900SS forks .