size stepper motor for cnc conversion of a mini-mill

I am trying to convert my mini-milling machine from Grizzly(G1005)
for cnc operation.

I like to directly drive the x, y and z axis with stepper motors (no
gear reduction). What torque rating stepper motor do I need?

The reason I didn't want to use gear reduction is the backlash
introduced by the gear train. Is this a concern I really need to
worry about? Also, would using belt and pulley solve the backlash
problem?

Lastly, if you have done this and have a web page describing your
effort, I would love to read about it.

-thanks
James