Board Thread:General Discussion/@comment-43505-20161008233233/@comment-1013969-20161010191923

The problem there is the Superman/Batman: Saga of the Super Sons collection has World's Finest 216 and 216, 221-222, 224, 228, 230, 231, 233, 238, 242, and 263 and the Elseworlds 80-Page Giant #1.

COIE:ABS is good for first issues but it doesn't always include all the issues involving the Earths it lists (and we have no idea what Earth-2B was supposed to be...might have been the "Alternate Earth-Two" in The Official Crisis on Infinite Earths Index but that is an assumption and it just muddles the Superboy issue even further)