What was found
PILOT REPORTED COMPLETE AIRCRAFT ELECTRICAL POWER FAILURE. ATTEMPTS TO LOWER LANDING GEAR USING BOTH NORMAL AND EMERGENCY PROCEDURES FAILED. ELECTRICAL POWER FAILURE WAS TRACED TO A FAILED VOLTAGE REGULATOR, TOTAL HOURS 450. LANDING GEAR EMERGENCY EXTENSION LEVER DID NOT DEPRESS FULLY TO ALLOW MANUAL RELEASE OF HYDRAULIC PRESSURE TO PERMIT THE GEAR TO FREE FALL. A MOLDING COVER TRIM RETAINING SCREW BACKED OUT RESTRICTING FULL LEVER MOVEMENT.