i have a 1970 mustang and have replaced all the front suspension parts but the control valve and power steering ram. well after doing the tie rods, inner and outer, along with the idler arm, i took it to the alignment shop and while checking it out they noticed a lot of movement in the control valve pivot ball. they moved the wheels back and forth and it did have a lot of play, i then took it home and had the wife move the steering wheel back and forth and i could see, what looks like, a lot of play on the pivot ball inside the control valve. i bought a rebuilt one and after separating the old one from the pitman arm i checked the free play, in the pivot ball, but really cant feel any, at least it feels like the rebuilt one. should there be a certain amount of play in the unit when hooked to the pitman arm and the engine not running.