I guess I was a little distracted. I never thought I would do this. I caught myself after only a tenth of a gal. of gas. Luckily (I thought) the tank was below empty. My immediate thought was to drain the tank. Unfortunately there was about 4 gal of diesel still in the tank. The only problem was that my big adjustable wrench was nowhere to be found in my tool box. I finally loosened up the nut with a vise grip and a pipe for leverage. The drain nut was on real tight. The worst part was feeling like an idiot, while working on the problem. I never felt so small (and I barely clear 5' 7"), and my truck never looked so sad.