Steve Young -- I'm Rooting for Kaepernick ... Take Back Your Team!!! (VIDEO)

Steve Young has a message for Colin Kaepernick now that he's been named starting QB of the 49ers again ...

YOU BETTER LOSE YOURSELF IN THE MUSIC, THE MOMENT, YOU OWN IT, YOU BETTER NEVER LET IT GO. YOU ONLY GET ONE SHOT. DO NOT MISS YOUR CHANCE TO BLOW!!!

Okay, he didn't say that exactly ... but that's the essence of it.

"I want him to take this opportunity and stay with the 49ers."

There's more ... we also asked Young how he feels about passing on the Brett Favre cameo in "There's Something About Mary" back in the day.

PLUS -- did you know Young is a direct descendant of Brigham Young? It's true.