I would just add that whilst just removing rack clamps to remove and slide on new gaiters, should not effect tracking, it could affect alignment of steering wheel if the rack is not clamped back in exactly the same position.
Note however this gives you the opportunity to correct any assymetry in the full lock positions with regard to tyres rubbing on stays etc. The steering wheel may have to be re-aligned in such circumstances.
Strongly recommend you replace gaiters with the superior after market universal ones from car builder solutions if you have latest type rack.
