The show at the Civic Arena was July 1974. I believe you can find it in the ABB set lists (though the song order is probably not correct). They opened with Wasted Words, and the roof opened. They had 2 sets, and they closed the roof at half time, with the claim being sound problems. July 2004 was not Lamar’s first tour, for I seen them at Three Rivers Stadium 8/24/1973. Brothers & Sisters was new then.
Again, they opened with Wasted Words on 8/24/1973. They did 2 sets that evening as well (the set list is not correct). Boz Scaggs was the opening band. Les Dudek was his guitar player. Les sat in on Ramblin Man and Jessica, as he does on the album.
I hope this helps!