Justin Bieber Celebrating 21st Early With A Sweet '65 Lincoln Continental

Although its not March 1st yet, Justin Bieber is getting his 21st b-day started. His buddies surprised him with a sick '65 Lincoln Continental.

According to TMZ ... Biebs was rolling up and down the Sunset Strip Thursday night in style after his boys John and Sammy Shahidi surprised him at the studio with the completely restored classic. 

We're told the Shahidi's -- JB's partners in the selfie-app "Shots" -- spent around $20K and several months working on the whip which looks just like the one in "Entourage" -- one of Bieb's favorite shows.

Now he can mark that of his bucket list....