I'm guessing it's "Pink Cadillac" references that's the link...
...so Tuner 8: Willie Nelson, "Well, you're sitting back In your pink Cadillac..." from Dead Flowers
... and Tuner 4: Brian Setzer, "Cost me all of my money and my pink Cadillac" from Hoodoo Voodoo Doll
...and Tuner 5 might just be Clarence Clemons (intruder, but the sax is just as much part of the song as the lyrics), "I love you for your pink Cadillac..." from Springsteen's Pink Cadillac