I am almost too ashamed to admit this one, but here goes.
I bought my truck and was taking it through some mud just for fun.  Drove it out of the mud and all of a sudden the engine died.  We spent the whole night looking for probs or shorts in the ignition and everything, then all that had happened was that a connector from the battery leading to the fuse box inside the cab was disconnected.  I put the two end back together and then it fired right up... not one of my greater moments in life 

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