I just received my 1500 final drive for my 04 VL800 and will be removing the drive shaft this weekend and taking it to the machine shop. I have a diagram from the VR sight drawn by M50DAVE on May 2012. It shows how much to shorten the splines,.098 and how much to machine back off the shoulder .187. My question is, Viper has said the machining of the spines are not needed for the drive conversion as previously thought,so does the shoulder still need to be machined? Also why was it once felt that the splines needed milled and now they don't need it? Thanks for any response Viper or anyone with there thoughts too.