I just published my already done 1998/99 adaption of the American rules Volley & Bayonet (1st edition) by Frank Chadwick here on my revised website.
The adaption is particularly suitable for the simulation of large Samurai battles as Nagashino 1575, Shizugatake 1583 and maybe even 1600 Sekigahara. Anyone who wants to play the major battles, should look at the adaption here.
And below you will find the complete order of battle, and many other information for playing the Battle of Nagashino: here.