The Avett Brothers and the Quebe Sisters join Asleep at the Wheel for the first “Austin City Limits” taping of 2015. Photos courtesy of KLRU-TV / Austin City Limits. Photo by Scott Newton.

Asleep at the Wheel leader Ray Benson looked around the stage near the end of the band’s performance at ACL Live to kick off the 41st season of “Austin City Limits” and marveled that the age ranges represented ran from a fresh-faced 23 years old to a sprightly 92 years young.

That’s what can happen when you round up a bunch of special guests who love the music of Bob Wills, which has inspired younger generations in much the same way that it thrilled the originators of western swing many decades ago. On Tuesday, they all gathered to help Asleep at the Wheel celebrate “Still the King,” the band’s third all-star tribute to Wills, due in stores next week.

Among the ringers on hand were North Carolina indie/Americana sensation the Avett Brothers, who joined an abbreviated Wheel cast for “The Girl I Left Behind Me” and “Take Me Back to Tulsa.” Bob Crawford, usually the band’s bassist, switched to fiddle to pair with Avetts violinist Tania Elizabeth in a classic western swing “twin fiddles” arrangement. It became three fiddles on the latter tune when the Wheel’s Katie Shore joined in.

Fiddles were everywhere, especially when Fort Worth violin trio the Quebe Sisters joined in. They took the spotlight for “Navajo Trail” and “Across the Alley from the Alamo,” then stuck around when soulful singer Amos Lee took center stage for “I Hear Ya Talkin’” and “Sweet Pea.” Benson explained that he first connected with the Quebes on a previous Wills tribute project a decade ago, when the sisters were just embarking on their teen years.

The crowd’s biggest cheers, however, went to the other end of the age spectrum. Early on, 92-year-old saxophonist Billy Briggs, from Wills’ Texas Playboys band, drew a standing ovation when he came aboard for “Route 66” during the Wheel’s 10-song opening set, and he remained on stage for most of the night.

Near the end of the show, Benson welcomed Texas Playboys vocalist Leon Rausch, 88, and the audience roared when Rausch took the lead on a classic swing-blues number. Everyone joined in for the finale of “Texas Playboys Theme” and “Happy Trails,” bringing the stage count to 20 players, seven of them on fiddle.

That was supposed to be it. The theater speakers filled with Roger Miller’s “King of the Road” as exit music, but Benson couldn’t quite let the party end. “Y’all got somewhere to go?” he asked as he brought Rausch and the Wheel’s primary cast back out for a “Chattanooga Choo-Choo” that had some audience members swing-dancing around the big camera booms on the floor. “All My Exes Live in Texas” followed before the first ACL taping of 2015 finally wrapped, with Benson’s declaration ringing in the air: “We’re all Texas Playboys tonight.”