I was calling the "off" position neutral. Sorry for the terminology screw up.
It blows as soon as you turn the key to "start." Also, I had the key in the auxilliary (acc) position and turned it to off and it blew the fuse at that point as well. A friend said that he thought it might be a bad connection on the starter (?) Not sure on that one.
5.3 Vortec 4WD. Automatic.
Nothing replaced recently. Front wheel bearing in early April and a fuel pump last May. turn signals and running lights in January. That's the most I can remember.