seeking CNC conversion advice

I just ordered a Rong Fu 45 and am dying to convert it to CNC.
Basically, I know how to spell CNC, but that's about it. I'd like to
buy parts that are known to work either on eBay or from a surplus
house, put them together, and start using the mill! I do research
work all day long and much of the night and would rather not have to
re-invent the mill. I'm sure my questions have been asked many times
before, but any help would be greatly appreciated.

I'd like to use servo motors. What size, voltage, drivers, etc? Is it
feasible to drive the screws directly without belts and pulleys?
After the mill is CNCed can it still be used manually? Is converting
to ball screws a must? Is the same size motor suitable for driving a
rotary table? Can a servo-driven rotary table be accurately
positioned for jobs such as cutting gears?

That's it for now! Thanks,

Tom Cloutier