I used J.K. Moore [link]
and Phil Bourassa [link]
's works here.
J.K. Moore made John Stewart, Phil Bourassa has done Hal Jordan design, but as I wasn't able to find a picture of him good enough to work on it, I recreate Hal with Superman's body (also P.Bourassa) and a screenshot of Young Justice for the head. I did the same thing with Thaal Sinestro, and created a head based on Aquaman (always P.Bourassa) ! It was kinda like customize toys in fact ^^
I'll try to do the same with Guy Gardner ! And maybe for Simon Baz, but Salim Ryem already did it ^^ [link]
EDIT : And here comes Guy Gardner ! Even here, he refuses to get in line ! ^^
EDIT : Kyle Rayner is done ! I'll try to make a special file of him, with all (I'll try) of his costumes ! He as the greatest look ! ^^