As you make your rounds of the South Main Art Trolley Tour on Friday night, check out this show. … It’s an exhibit of photographs by the lovely and talented Drue Diehl, capturing one of the Memphis music showcases at South by Southwest this past March (this showcase, actually). Some of the pictures doubtless will depict Memphians — some of whom you may know — behaving poorly. Some of the subjects in the pictures may no longer be welcome in the city of Austin, or in the entire state of Texas. There could be some really historic stuff in there …