thanks guys, I love the unistack personally. Ya it just ends up off center as to where all the original exhaust hangers are. I wanted to do duals but if you want duals you have to have a Y pipe in the bed and it doesn't look good to me. I did it myself at a buddys shop, I got the kit and stack for 650, and only took an hour or 2 to install. The injectors will be getting swapped out in the next couple months, the LLY duramax just had problems with heating more then anything. the previous LB7 that was in the 01-early 04 had the injector issue and gm would cover up to 200,00miles or 7 years. But if you're passed either of those then I've heard you're looking at about a $3600 bill.
When in doubt, Smoke em out.