Hey I’m new here and have a few questions on deleting my 2013 lml duramax. It is completely stock and I’m unhappy with my mpg’s I average around 13 on a good day and am looking to increase that. I have been looking at delete kits on eBay and have found a plethora of kits mainly utilizing efi live. Here come the questions, do you think eBay is a good place to buy these kits? Should I do a full exhaust or delete pipe? 4in or 5in exhaust? Do I need to install blocker plates on the egr or does the tuner take care of that? Do I have to unplug anything on the egr? I think that’s it, thank you in advance.