I contacted the dealership. They are the 4.6/4.8 tips. I have a few questions which they weren't able to answer... hopefully you guys can provide the help.

1) Do I need to order anything else to install this on my 2001 3.0i?
2) How is the installation? Is it welded or bolted? How much will installation cost?
3) Are the tips purely cosmetic? If i want better air flow and sound, will I need the entire exhaust?

Thanks guys. Sorry if any of these questions are repetitive....