The rack?

On a 1993 nissan sentra, can one change only the rack with changing the pinion? Can someone show me a picture of the rack, or describe where its at and how to get it off? Is the rack the same thing as the steering gear? Or is there another name for the rack. I'm told this is what is wrong with the car cause there is a leak underneath and its power steering fluid.

it's all one assembly.
see the link:

http://www.partsamerica.com/ProductList.aspx?PartType=252&PTSet=A

yeah...the rack and pinion is all one unit and is used instead of the steering gear. the rack is just a metal bar with angled teeth on one side. the pinion is the gear that drives the teeth so the bar moves left and right, turning the wheels.