My warrantee is out on my 12 so I want to look at a tuner and exhaust work on my truck. I'm not really looking for max HP I just want the mileage increase from eliminating that recirculating crap. The local truck shop wants $3000 to do this. Is this something I can do myself with the right parts. What systems work the best for fuel mileage without putting a strain on my motor or injectors. Who is a good source for info and parts?