need help with tos milling machine

Hello everyone I have a tos fnk25 vertical milling machine and wish to convert it too cnc .I am a bit stumped as regard the size of stepper motors, I require, can anyone help?

here are some figures i worked out
require 640oz/ins when load applied to x axis
would like to have 2 to 1 gearing
max 833 steps/second with gearing
according to gecko site
this relates to 163 watts of power need to move the axis
833 x 640 divided by a factor of 4500 plus 40 percent
have i work this out right?
how do i now pick the most efficent motor?
if i go oversize on the stpeper motor .can i reduce the voltage to compensate thus reducing the power?

all the best Derk on the Isle of Wight (uk)

Googled TOS FNK 25 CNC Conversion and this was pretty much the only post I could find....

What's the most random part of it, is that I also live on the Isle of Wight and didn't realise Derk was doing a conversion on the same machine.

Has anyone else done one since?

Cheers