Just an idea I got the other day...
I was running an endurance race on Gran Turismo 4 (which took me 3.5 hours!) when this little thought struck me - maybe Mickey Gunn could be a bit of a gearhead/petrolhead (both terms mean people obsessed with anything with a motor, cars in particular - the first one is American and the second one is British). Additionally, he could have a really awesome classic vehicle (don't worry, I'll pick a good one!).
I think this didn't just come from Gran Turismo, though. I've spent much of the weekend attempting to tell the Beatles apart, so the car thing may be partially inspired by George Harrison. (He liked Minis, though, and they're just the best things ever, as the models scattered around my room testify). Mickey seems more like the muscle car type, though, so I was thinking he could have a Pontiac GTO or a Chevrolet Camaro - maybe even a Ford Mustang if he's into pony cars. He looks like a GTO guy to me, so right now I'm thinking he'll have a Goat. Just wanted to toss this one out there.