Digital Machinist Magazine did a total upgrade of the Emco F1 mill, written by Eugene N. Niegoff. I bought the 4 back issues; winter '06, spring 07, summer 07 & fall 07, for about $26. The info was worth it, in my opinion. He upgrades using Mach 3 OS and Gecko drivers. I recommend reading this before beginning your project. He covers the spindle motor upgrade, also. I haven't started my upgrade yet, and I have no connection to the magazine, other than being a subscriber.