If any change from the location described in the conveyance instrument is found to be necessary on account of engineering difficulties or otherwise, amended maps and field notes of the new location shall be filed, and a right-of-way for such new route or location shall be subject to consent, approval, the ascertainment of damages, and the payment thereof, in all respects as in the case of the original location. Before a revised conveyance instrument is issued, the applicant shall execute such instruments deemed necessary by the Secretary extinguishing the right-of-way at the original location. Such instruments shall be transmitted by the Secretary to the office of record mentioned in Sec. 169.15 for recording and filing.