just bought my 2005 LLY duramax and was wonder what suggestions/input anyone may have as far as taking off my cat converter and what to put in place of it. i'm looking at a dual 4" stack kit from XtremeDiesel.com but am not quite sure if this will bolt right up after i remove the cat. also i'm looking to put in an egr blocker plate. how would i would go about doing this? and will it throw a code?