If memory serves, he only did the last couple pages of 'Aires 78, introducing the Blight. Most of the issue was by Moy.
not much was going on in the issues leading up to this. there were some fights with Bizarro Legionaires, a lizard gangster on Rimbor, some elemental creatures trying to wake up Mordru but failing, and a Shazam-esque Legionaire from the far future named Thunder collecting pieces of the destroyed Rock of Eternity.
The Amazers, the heroes of Xanthu, wound up visiting earth in time to be Blighted. I can't remember why.
And In 78, Robotica is introduced.
If you have Legion Worlds #1, the back-up feature (by Coipel) shows the current roster of that time. so does Legion SEcret Files #2, which came out about a half-year before Coipel began (he does a one-page on the Blight).
FRom memory, membership at the time was:
Cosmic Boy, Live Wire, Saturn Girl, Triad, Apparition, Invisible Kid, Chameleon, KId Quantum, Star Boy, Violet, Brainiac 5.1, Ultea Boy, M'Onel, Ferro, Karate KId, Sensor, KInetix, Thunder, Gates, Umbra, Spark, Element Lad, and I'm probably forgetting someone.
NOT YET MEMBERS were Dreamer, Wildfire, Timber Wolf and Skakari, the latter two hadn't been introduced into continuity yet.
not members, but very present: Dreamer, Chuck Taine and Dirk Magz (a formerly magnetic Legionaire who lost his powers. he ran the Legion's orbital space station), kid sidekick Lori Morning, Tenzil Kem (the Legion's chef), Lt. Shvaugn Erin, and "Drake Burroughs," not yet Wildfire or even ERG-1, recently manifested as a single life-form from two entities named Drake and Burroughs, who "died" fighting Mordru back arounf 'Aires 50.