First I'd jack the front up (both front wheels) and then try turning the steering wheel from side to side without the engine running....if that feels OK then I'd try starting the engine and move the wheel from left to right half a dozen times - this will remove any air from the system. If the rack came from a wreck it is possible the rack itself was bent/distorted in the prang.....the first check should show that. Other than that, the only thing I can think of is that somehow the camber adjusting bolts have been moved.
Good Luck.
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