You can do almost anything. You may not care about Navy regs and sop but don't cross the line. You aren't untouchable. The FAA could still violate you. If you want to fly professionally after that "last flight" might not want a violation on your record. On the other hand, we had a chief pilot flying a ceremonial last flight in the A300 that was also his retirement flight. He got so low over Miami Beach the Feds came after him. BFD! He retired like a Demi Prince and mandatory retirement at 60 (then) had already ensured he would work again as a pilot.