As far as Custom muscle cars go, Ringbrothers are at the epitome of building some incredibly juicy ones. And while one would think that they’d eventually hit the ceiling on pushing the boundaries, these guys surprise us every time by bringing out even more stunning examples. For this year’s SEMA Show, Ringbrothers have once again presented the world with a stunning one-off classic custom in the form of the 1969 Mustang Mach 1 that they call “UNKL”.

UNKL is powered by a 520-cubic-inch (8.5-litre) Boss engine that produces 700 horsepower and is connected to a Bowler six-speed Tremec transmission that sends power to the rear wheels via a QA1 carbon-fiber driveshaft. The custom 69′ Mach 1 sports a custom stainless-steel Flowmaster exhaust that can imaginably produce enough ruckus to upset environmentalists on the other side of the globe.

Alongside the performance upgrades, Ringbrothers have given the Mach 1 Mustang a cosmetic facelift too. The body has been extended by an inch on either side. The car’s body is now a mixture of carbon-fiber and steel panels reshaped by Ringbrothers for lightness and rigidity. Billet taillights and reshaped bumpers have been added alongside machined parts custom made in-house by the Wisconsin-based custom builder.

UNKL uses Detroit Speed Engineering’s Aluma-Frame front suspension system with a cast aluminum cradle, custom-tuned steering rack, tubular suspension arms, custom adjustable RideTech coilovers and front/rear sway bars. The rear gets their QUADRALink suspension system and RideTech shocks. Braking is done via Baer 6S Extreme calipers, while the custom build rides on bespoke set of forged HRE Wheels wrapped in sticky Michelin Pilot Sport 4S tires.

Everything about this build is special. It’s inspiration coming as a tribute to the owner’s uncle who instilled him with a passion for cars, to the poise of the classic muscle with it’s modern internals, UNKL is a unique perspective into the art of custom building old-school metal with a hint of modern charm.