Duff McKagan has worn many different name tags and hair nets: SW scribe, co-founder of Guns N’ Roses, father of two. But lately he’s been relishing what is possibly his most powerful gig yet: Grand Marshal of Seattle Seafair. As he wrote last week, Duff’s got plenty of tasks to take care of during his reign. And the position is already getting him good seats to see the M’s: before Thursday’s contest against the Red Sox, Duff will throw out the ceremonial first pitch. Get there early to cheer him on, and report back on his skills behind the mound.Good luck, Duff.