Some time ago, a user named @AshelyAshes uploaded what little was found of Gurren Lagann's ADV dub. However, due to a muxing error, episode 3's audio track's actually a repeat of episode 5's.
A great pity, given that the user later corrected that episode, yet it was never uploaded as of late. Fortunately, I've been able to download that torrent, and am sharing the episode files for all to see. Also, @AshleyAshes, we'd greatly appreciate episode 3 of Gurren Lagann's lost ADV dub.