On November 25, 1998, at 1040 hours Pacific standard time, a Grumman-Schweizer G-164C, N6596K, made a precautionary landing due to a dislodged rudder pedal and ground looped after touchdown at the Oroville, California, airport. The aircraft, operated by Chuck Jones Flying Service, Inc., as a positioning flight under the provisions of 14 CFR Part 91, sustained substantial damage. The commercial pilot was not injured. Visual meteorological conditions existed and no flight plan was filed. The flight originated from Biggs, California, and was scheduled to terminate at Corning, California. The pilot reported that he attempted to adjust the right rudder pedal while airborne and the pedal's stop failed and the rudder pedal and brake became useless. The pilot stated that he attempted to resecure the rudder pedal for several minutes and when his attempt was unsuccessful, he diverted to the Oroville airport due to a longer runway. He reported that on the landing rollout, cross control had to be applied to compensate for the loss of the right rudder control. The aircraft drifted left of center and the locking tail wheel did not lock. The pilot reported that the left turn increased and the aircraft then began "crow hopping" to the right. He stated that the right gear failed, the right wing and propeller struck the ground, and the aircraft came to a stop. The pilot stated that there were no other mechanical malfunctions noted. The chief mechanic for the operator stated that the rudder adjustment is a manual mechanism, located down by the rudder pedal that consists of a pin and a plate that has holes in it. The plate also has two 90-degree tabs on either side of it. These tabs should prevent the pin from becoming dislodged. The pilot would have to bend down and reach under the dash to gain access to the pin to readjust the rudders. Once the pin has been pulled for readjustment, it is possible to push the pin past the tabs, making the process of moving the pin back into position very difficult. The Federal Aviation Administration (FAA) inspector who examined the aircraft stated that the rudder is physically locked into place with a pin. This attachment has holes on the left side of the plate and the right side is where the pin is located. When the pilot attempted to readjust the rudder he "pushed the mechanism too hard and the rudder plate went all the way back underneath the dash." The FAA inspector stated that the pilot would have had to physically go under the dash to rectify the situation. The FAA inspector further stated that there is not a stop device in place to prevent this from happening.