Darkside Customs has built ground-up Harley-Davidson customs and serviced American V-twin motorcycles in Santee since 1989, operating from the Prospect Avenue industrial corridor. Custom builds leave the shop fitted with Precision Machine brakes and billet controls, premium components sourced through the corridor's aftermarket pipeline that includes Autoworks Parts on Prospect Avenue. The fabrication bay also handles truck suspension lift-kit installations and high-performance engine work, extending the shop's capabilities beyond two-wheel platforms. Completed builds undergo custom paint and show-detail finishing before delivery, a final presentation stage that feeds into the same East County automotive-aesthetics corridor where Dali Detailing handles paint correction on Woodside Avenue. Ground-up Harley frames incorporate nitrous-oxide delivery systems, hand-fabricated sheet metal, and custom drivetrain geometry tuned to each client's low-profile, high-torque specification.