This morning’s “Mitch in the Morning” show on KJR took up an interesting topic: whether Randy Johnson will enter the Hall of Fame with a Mariner or Arizona Diamondback ballcap on. To gain a somewhat objective perspective, host Mitch Levy called a couple sporting goods stores in the St. Louis area, asked the employees on the other end of the phone to close their eyes and picture Johnson on the hill, and then tell Levy which jersey they saw him in. Both responded that they envisioned Johnson in a Diamondback jersey (granted, St. Louis is a National League town.)If you go to the tape, well, either tale could be told. Johnson spent his most time and won his most games (130) in Seattle, helping lead the franchise out of a terminal malaise and into perennial playoff contention. Seattle was also where Johnson, previously a wild child in Montreal, established himself as a dominant pitcher; he won the American League Cy Young Award in ’95.But it’d be hard to argue with the Unit if he chose to enter the Hall as a D’back. It was there where he won his only World Series title, a dramatic seven-game triumph over the Yankees in which he was the MVP. He posted a regular season record of 103-49 during his Diamondback tenure, and won four Cy Young Awards, clearly establishing his time in Arizona as the most dominant stretch of his career, and cementing his Cooperstown qualifications.Sure, we love the Unit in Seattle, as evidenced by his emotional farewell a couple weeks ago when the Giants (his current employer, with whom he just won his 300th game) swung through town for the final time in what is almost sure to be Johnson’s last year. But I’ll bet the love he gets in Phoenix is at least on par, making the Unit’s induction-day wardrobe decision a real toughie.