Easy Directions. Fullerton Location. Val Mesa Medical Building 100 East Valencia Mesa Drive, Suite 215 Fullerton, CA 92835 Phone: 714-912-2211. Newport Beach Location. Newport Center Medical Plaza 1441 Avocado Avenue, Suite #309 Newport Beach, CA 92660 Phone: 714-912-2211Meet Dr. Gunn‧Personalized Care‧Medical Services‧General Health Articles‧Patient Forms‧Blog.