NTSC in and out of resolve

Is there a trick to getting ntsc 720x480 29.97 in and out of resolve? no conversion, just what goes in comes out.

I don't get what trick is needed?
It's just resolution/fps as any other.
There are Timeline Resolution preset for it, but you also have to set correct Timeline Fps, which is very important part!

You ought to upgrade to at least 14.3, as you may not be able to work with interlaced SD footage successfully with 12.5. For export, look to the Grass Valley codecs.