Header installation on a 2002 Lexus IS300 using the factory y-pipe.
Aftermarket OEM style gaskets 31332 used and were purchased at Napa auto along with grade 8 bolts/nuts/lock washers.
Purchased header at http://www.remixcustom.com/1-exh-lxis... since the ebay ones (probably the same exact ones) suddenly jumped up to $450 in course of a few weeks.

I will be doing a video on how to wire the o2 simulator to get rid of the check engine light once it comes in.