What was found
DFW - ON APPROACH GEAR HANDLE STUCK IN *UP* POSITION. HANDLE WOULD NOT *PULL OUT* NO HANDLE MOVEMENT AT ALL AVAILABLE. WENT AROUND. STARTED CHECKLIST AFTER STABLE AT 4000 FEET AND CHECKED HANDLE ONE MORE TIME AND GEAR HANDLE AND EXTENSION WERE NORMAL. NO FAULTS NOTED. EMERGENCY DECLARED LANDED DFW WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. FOUND GEAR LINKAGE BEHIND CENTER DASH RUBBING ON STIFFENER. REPOSITIONED STIFFENER. SYSTEM GROUND CHECK NORMAL OPERATION.