ATA 27

Westwind Service Bulletin 1124-55-150 Rudder Inspection
We recommend that the rudder be removed from the aircraft for this inspection due to the number of x-rayshots required and the height from the floor that the camera must be lifted—it could make a big dent in stabs and elevators!
If crack indications are found on your rudder, find out from the NDT tech which side they are on. If he’s good, he can tell you. If he says right, you may be in luck. It seems that the factory assembled rudders with narrow ribs and installed a whole bunch of 0.025 shims on the right-hand rib flanges to make the skin come outeven. Where the shims intersected stiffeners, flanges, etc., the hole was dimpled. It now shows up as a crack inthe rib. We found this exact problem and replaced the stiffener/shim and saved the customer the cost of an exchange rudder.
Bear in mind that there can still be cracks in left rib flanges and skins, but find out for sure before making your decision.