It helps a lot if you have someone with you so that that person can wiggle the steering wheel while you get underneath and look. Have the wheel person move the wheel slowly back and forth just a few degrees, with power off, wheels on the ground, and start checking down the line for lost motion, starting with the u-joints in the steering column. There may be a little in the steering gear itself, but there shouldn't be much. A little bit will be present with power off but it should tighten up some when it's running. The sterring gear may also make a little clicking, but that's not necessarily bad with the power off. Sometimes bearing play in the output shaft of the steering box will cause slop, so make sure it isn't moving sideways before it starts to rotate. Then just keep looking at all the tie rod and drag link ends. Bad tie rods are usually pretty easy to spot if you jack up the front end and try steering by pushing on a wheel.
