Hey ZVO, installing a new Fullsac System takes about 4 hours if you take your time and do it right, I am an average mechanic who takes more time than necessary, but when I am done its right and it took me about 4 hours, I had a great time doing the upgrade. In the end, I did call Steve at Fullsac to help me with the final connection and ECM download from my Laptop, he was great to work with, very patient and in the end, my 2012 FLHTCUSE7 runs GREAT !!!! Like someone else said, the grinding out of the original baffle welds is a PITA, but again, have the right grinder and a new carbide grinding tool, take your time and it will work out fine. I do recommend the new baffle screens inside the factory muffler that holds the packing up against the wall of the factory muffler, they work great !! Again, someone else recommended Youtube, especially for the weld grinding, it will help. Good luck with the Fullsac Mod, you won't be disappointed !!!