the 04-05 trucks had a different leaf pack from the factory which made them sit up slightly higher than the 06+ trucks in the rear.

general rule of thumb:
04-05 = 2.5" level
06+ = 2" level

 

I'm thinking about getting a smaller block on the rear end on mine. Mine is a '04 too and my bilsteins just don't level it like I had hoped. Like you, I thought about putting them back at zero setting, but it will be alot cheaper and probably quicker just to get smaller block. If you do decide to do this, take pics I would like to see how it looks, so I can decide if I go this route.

 

I'm most likely gonna do the blocks like we are saying. I'll measure them and report back. Pretty sure I have 2" blocks.

I'll report back, thanks for the help so far.