New to the Duramax, Where is the block heater plug located on the 04 ??

ITs on the passenger inner wheel well (on the plastic water/mud cover) ITs tied to a cable that runs down to the motor.

and it is barely long enough to get it out the front. I pulled mine through under my headlight. I don't like the banging on the hood.

Thanks guys, My Powerstrokes were easy to find.

I had to put it through under the head light as well as to not damage the paint on the hood. and I know what you mean with powerstrokers, I had 4 till I came to my senses and went back to my old school of CHEVY.