Buying an Old Lathe to Retrofit... Worth the Effort?

I was trolling eBay, and happened to do a completed items search for metal lathes of 10"
swing and smaller...

I noticed DOZENS of older South Bend (and others) 9-10" swing, 18-30" bed lathes having
sold for under $500 or so...

That kinda got me to thinking... (which is usually dangerous).

Turning an old lathe into a "hobby class" CNC machine would involve (roughy speaking, of
course!), stripping off most of the drive gears to be replaced by a Stepper/Servo drive.
Replacing the Acme lead screw with a balls screw. Probably removing the compound.
Maybe replacing the AC motor with a DC motor and speed control. and the usual cleaning
up..

So really, if it's got good bearings in the headstock, and the ways are good...

Would it be worth doing, I wonder?
It's a lot of work, yes... but a guy could either start with his "good" lathe (a chinese import
in my case.. and bigger than I need in a CNC, requiring a longer expensive ball screw, and
bigger more expensive motors)..
OR he could get an older South Bend Model A (for example), strip a lot of the parts that are
worn, rusty, or useless..
And go from there.

And for reference, I'd put forth an accuracy standard of " +- .002".. since that's what I can
hold on my chinese "Centre Machinery" Lathe...

Curious to get opinions... Not thinking of jumping out and doing it IMMEDIATELY...
Paul F.