InVince-ible: MCA's Vince Gill was named an ambassador for Chattanooga's Songbirds Guitar Museum, the world's largest private collection of rare, vintage guitars. He'll perform at the museum's Mar. 9 Grand Opening Celebration. "This is the most impressive collection of rare, vintage guitars I have seen," says Gill, who will curate some of the exhibits. "I am honored and excited to be a part of such a tremendous display of music history."