Is your car a 4.6 V8? I should have asked that originally.Tried a 10mm fit real loose, started to round, tried 3/8 6 point broke the socket. These are froze on. Soaking with penetrating oil.
Ok, I apologize. I incorrectly assumed that you had a 4.6. You'll need comment from someone who has the 5.0. That isn't my area of expertise.92 Sport 5.0 V8