tw2

Are they longtube mid or shortie headers? There is no doubt that it can be a fairly crappy job. If all bolts are seized, exhaust studs come out etc it could take ages. If all goes well then I would think 5-6 hours is a maximum for a reputable shop especially if they test it for leaks and torque all the bolts correctly.

Jacob Goodapple

They are equal size shorties. My car has 133k miles, so there could be some issues... but I am in the right thought that a minimum of 6 hours and more likely 9 hours is a little excessive, right?

tw2

Yes i think it is excessive. I could probably do it in 9 hours with handtools and my floor jack.