Removing an Indigo ring from an individual seems to be almost the same as removing a Red ring. Guy Gardner was submerged into one of Mogo’s pools after the Blackest Night event in order to purge him of the Red Lantern ring.
From – Green Lantern Vol. 5 #11
I’m a bit confused about Hal’s ring. What happened to the one he made out of his own will?
This is from the New 52, so it’s before he made the one from pure will. 🙂