Conglomerate of comments are the way to go, thread chaser, wire brush, acetone. One exception is Ive never heated to remove loctite but I worked a furnace so heating to remove loctite was never a concern. A good pen oil like liquid wrench w/ a thread chaser after a good wire brush acetone clean will fix any female thread that can be fixed that I've met. That said you can certainly make fucked threads work with enough torque and stupidity.