We've had many question being able to use PowerLight in the NavLight port at night. We believe you can! As long as you're using your trolling motor, (of course you make the final decision). Check out US Coast Guard 33 CFR 83 to help guide your decision. (If your power-driven vessel is less than 23 feet (7 meters) in length and its maximum speed does not exceed 7 knots, then it may display an all-round white light.) Therefore, it appears you can use the PowerLight in your front navlight port while fishing at night with trolling motor with white light on back. https://www.uscgboating.org/images/420.PDF