Which magnaflow exact pieces you got?Great questions. He cut the old cat out and then welded the magnaflows (two connected together) into the gap. It took him less than 45 mins in and out. I have 231k miles on my LC. I feel like a may have a little more power as well. However, my mileage has increased substantially. Good luck.
I wonder if you were able to pass smog check after that? I am in California which has more restrictions. Thanks