A quart/liter should do it; a pint won't. If you're buying Penrite, 2 bottles.
When you're filling the steering box, be sure to turn the steering wheel lock to lock a few times so it settles in properly - otherwise it will appear as full when it's only half full.
I found it convenient to heat up the grease in the microwave, then use a turkey baster to inject it into the box.