I agree with Bruce Thomas that Harry Manning appears in at least one scene in this film clip. Contrary to what some of the internet articles about the film clip say, I don't see Fred Noonan anywhere in the film clip. Manning but no Noonan points to an early March 1937 date for this film clip. Noonan was not added to the flight crew until shortly before the first world flight attempt started, to be the flight navigator while Manning shifted to being primarily the radio operator.
There are other clues about the aircraft in the film, in addition to the presence of the trailing wire antenna deployment tube and weight mentioned up-thread, which clearly indicate this film was shot in March before the first world flight attempt. The forward mast for the dorsal V-antenna on top of the fuselage is well aft of the cockpit overhead hatch. On the underside of the fuselage, masts for two belly wire antennas (port and starboard) are visible in the film clip. These two features -- aft position of dorsal V-antenna mast and two belly antennas -- were present for the first world flight attempt but not for the second world flight attempt. For the 2nd world flight attempt, the trailing wire antenna was removed, only one belly antenna was installed, and the forward mast for the dorsal V-antenna had been moved forward to just behind the cockpit overhead hatch. (There were also changes made after the Luke Field crash to the arrangement of the feedline from the radio transmitter to the starboard leg of the dorsal V-antenna. But the feedline was on the starboard side of the aircraft, and we can't see any of it in the Bresnik film clip.)
Additionally, an early scene in the film clip shows the Electra parked on the tarmac with "spinners" installed over the propeller hubs. (The "spinners" are the aerodynamically streamlined caps placed over the propeller hubs.) The spinners were installed for flight testing on March 6 and 7 to measure fuel consumption rate of the Electra's engines, tests conducted by Kelly Johnson with Earhart piloting. As far as I know, the spinners were installed only during this testing in early March and were removed shortly afterward, never to be installed again. There are several photos reliably dated to 6 or 7 March which show the spinners installed. One of these photos is the quite well known photo of Amelia and George Putnam posing in front of the Electra and holding an emergency kite.
Every relevant detail in this film clip points to a March 1937 date, probably March 6 or 7, for when this film was shot. Nothing in the film clip suggests a May 1937 date. Sadly, whatever research and fact-checking/editing were done in the preparation of the associated book about the film clip apparently didn't include talking to anyone who has studied photos of Earhart's Electra and actually knows something about the history of her aircraft and the timeline of the changes which were made to it.
Jeff P.