Introduced in 2003 and developed in conjunction with the McLaren Technology Centre, the Mercedes-Benz SLR McLaren paid homage to the immortal W196-based Mercedes-Benz 300SLR of 1955 Mille Miglia fame and the original 300SL. As production was nearing conclusion by 2009, 150 examples of the 722 S McLaren Edition were produced to commemorate the record-setting 1955 Mille Miglia victory of Sir Stirling Moss and his navigator, legendary Motorsport magazine columnist, Denis Jenkinson. This example is No. 6 of 25 McLaren Edition SLRs produced; of those, only six of the 25 were Roadsters, with this being the only U.S.-specification example. Originally ordered and commissioned by professional boxing legend Floyd Mayweather Jr., it was initially produced as a U.S.-specification 722 S Roadster and later shipped to McLaren’s U.K. headquarters in Woking, Surrey, to the new company’s MSO (McLaren Special Operations) division for conversion to a 722 S McLaren Edition Roadster. Furthermore, it carries unique status as the only one to receive many unique mechanical and cosmetic upgrades at a cost of over $1 million. Featuring butterfly-style doors and unforgettably finished in one-off, two-tone McLaren Orange and black paint, this bespoke supercar also sports carbon fiber additions, including the door sills, new front fenders, the decklid with an adjustable wing, side-view mirrors, front spoiler, hood slats and underbody with an upgraded rear air diffuser. Interior enhancements include exclusive black Nappa leather upholstery with microfiber inserts, orange stitching, seatbelts, trim, seatbacks and embroidered McLaren insignias. The 5.4L M155 V-8 engine is rated at 750 HP and, in addition to its Lysholm twin-screw supercharger and dry-dump oiling system, upgrades include the engine management software, intercoolers and a McLaren sports exhaust—all features not found on the other 722 S McLaren Edition Roadsters. The renowned AMG Speedshift 5-speed automatic transmission delivers the massive power output. Stopping is via the 722 S-specification larger carbon ceramic disc brakes over those of the “standard” SLR, with this car featuring McLaren Orange-finished 8-piston front and 4-piston rear calipers. The specially tuned suspension includes stiffer springs and shocks, plus a lowered ride height. While built for ultimate performance, this one-of-one 722 S McLaren Edition Roadster is comfortably equipped with dual-zone automatic climate control, a shift knob-mounted start button, fog lights and brilliant Xenon headlights, tinted tail light lenses, the SLR McLaren’s signature side-exit exhaust with black-finished pipes, and 19-inch multispoke wheels. Documented with paperwork and receipts from McLaren and the original books and manuals, this bespoke supercar also includes a tool kit and car cover.