First, does your have the little hydraulic dampener attached to the tension idler ?
Some 2004 models do.
At any rate, all you need is a 17 mm socket and wrench or pull handle.
There is a 17 mm extrusion on the bottom left of the idler where you connect and turn CCW, this will relieve the belt tension.
You can also insert a proper size hex wrench into a supplied hole when you fully rotate the idler to keep the tension relieved, but most don't bother with that.
When putting the new belt on, get it in the grooves on all the pulleys, the last thing you do is then do the tension relief again and place it over the idler pulley.

Another option is driving 131 miles to my place and I'll do it for you