Great find, I haven't seen that video before. Re -the high bass line, this is done fairly much throughout Pet Sounds. GV is recorded in his "sections" style.
I'm a big Brian Wilson devotee myself ... enough to know I shouldn't emulate him in anything I do on Sonar.
The Pet Sounds sessions highlights are an enlightening demonstration of Brian's studio techniques, along with the "Behind The Sounds" series available on YouTube, for example
https://www.youtube.com/watch?v=X3f6ZKQ_ffo Also see the way Brian arranges that magical intro to California Girls at
https://www.youtube.com/watch?v=c4IcDgNRPQ4&t=142s (who would chance an intro of that duration these days?)
He did all that on four track at the age of 23.
A good insight into that and other musical genius is demonstrated on the film "The Wrecking Crew" - the LA super sessions group (Hal Blaine, Carol Kaye, Tommy Tedesco, Glen Campbell, etc).
And then there was Smile, fairly much all in sections ...
jdf