You can do it with the lines on the car if the rest of the lines are mostly filled with fluid. Slide some vacuum line over the new lines and fill them up with fluid. Then hook up to the master cylinder and get most of the air out of the four corners.
Crack the lines loose at the master cylinder and run them like they are bleeders. Gotta wrap rags around the lines in the car and put a pan under the master cylinder... some drip will find paint. Hold pressure, crack the lines loose fluid and air will bubble out of the threads. When it is just fluid, go bleed at each corner again.
Its easy enough to do, but if you can bleed it on the bench do it as its a lot easier. The above works if you don't have some spare lines. (I figured out how to do it on a master that had a remote resevoir and I had nothing that fit the ports!