I removed them when I did the valve job on a friends. I used a socket that fit in the tube snug and used vise grips and turned it and removed it. They are a snug fit. I used sealer and drove them back in. The manual says to destroy them so they can sell them to you. Likely leak is the seal at the valve cover end.
2000 300M Silver, HID's, RB1, Sirius Radio, 6 CD Changer, 2002 wood wheel, EVIC with PSI, Steering wheel radio controls, 2002 12 spoke chrome wheels, 2002 mirrors with tiltdown and auto dim, Mopar spoiler Most Clean at Kansas City 2006, Members choice at INDY 2007 and Most clean at Carlisle 2007 & 2008 Most Cruising Carlisle 06, 07 & 08. Most Clean at Indy 2009 Almost Clean at Carlisle 2009 & 2010