According to Boones WC testimony, FRITZ was the one who lifted the rifle by the sling from its place.
There’s no mention specifically naming Lt.Day by Boone, the “ID” man cannot have been Lt.Day if Tom Aleya statement is correct that Lt.Day did not arrive to the 6th floor until 18 minutes after the rifle was photographed.
Boone used the phrase “At this time” referring to when the photo was taken, that Fritz picked the rifle up “from its place”, so either Boone has very bad memory, OR a rifle was lifted up FIRST by Fritz almost immediately after the photo was taken, and then LATER , when Lt.Day arrives, the rifle has been either moved to or returned to”it’s place” to be lifted AGAIN by Lt.Day while Aleya films it.