I also give the nod to Performance Technic:
https://www.performancetechnic.com/ They performed the PPI when purchasing my car from a forum member here. They have
extensive experience with the S65 and do everything from maintenance to street builds to full out track builds. Highly recommended.
EDIT: Look what happens when someone resurrects a thread nearly a year dead. Note to future self: read the date of the first post.