The inking was formerly credited to Mike Royer. Colletta attribution is confirmed in “The Thin Black Line,” page 83 and by the Kirby Museum:
http://www.whatifkirby.com/news/forever-people-issue-6-cover-photocopy
http://www.whatifkirby.com/news/new-creation-forever-people-issue-6-cover-…
The second link shows a more recent cover re-inking by Royer alongside the Colletta cover.
Inks credit from Scott Grammel. Royer lettering per Nick Caputo; previous indexer credited John Costanza.
Includes letters from Bob Rozakis, Mike W. Barr, Bruce Long, John Cameron, James Kaston and Greg Hendrickson.