Who do the hands that help form Naruto's Final Rasengan belong to? Here is the video of Naruto's Final Rasengan in episode 477.

The hands of many friends, parents, and teachers of Naruto Uzamaki were shown shaping and enlarging together his Rasengan:



My questions are:


What is the meaning of this scene?
What is the chronological list of characters of the Naruto universe who contributed to his Rasengan (with irrefutable evidence)?
This has been going around Twitter for a while.

This is more or less Naruto's version of the DBZ Spirit Bomb trope where you borrow the spirit of all your allies into one final coup-de-grace. Then hands represented are as follows:
Left column (clockwise):

Jiraiya
Minato
Kushina
Shikamaru, Ino, Chouji

Middle column (clockwise):

Hinata, Kiba, Shino
Lee, Tenten, Gai (charred by the 8 Gates), Neji
Gaara (Fifth Kazekage), A (Fourth Raikage), Bee, Tsunade (Fifth Hokage), Mei (Fifth Mizukage),  Ohnoki (Third Tsuchikage)
Hiruzen (Third Hokage), Iruka, Konohamaru

Right column (clockwise):

Sai, Yamato
Obito
Kakashi
Sakura