I wasn't going to reply, but I will. ( heh )
That photograph is a modern representation of the formation. I'm looking at this from the time period.
"The formation consists of a flight of four aircraft, composed of a "lead element" and a "second element", each of two aircraft. When
viewing the formation from above, the positions of the planes resemble the tips of the four fingers of a
human right hand (without the thumb), giving the formation its name. "
Middle Finger Lead
Index Finger #2
Ring Finger #3
Pinky Finger #4
Now, there's nothing wrong with a reverse-finger four depending upon circumstances, but historically, the above definition serves the WW2 era.
Vik
Diamond
Eschelon L / R
Line Abreast
Line Astern
Finger Four
It's not a HUGE deal, merely pointing out an inconsistency from the original definition of what a Finger Four formation was in Ww2, from what I understand.