Perhaps not a true production car, the M6 GT has the honour of being McLaren's first road legal car nonetheless.
The road car story starts with the M6GT (a modified M6A Can-Am car) of which three were produced by McLaren's partner Trojan. They were technically road legal, but realistically classed as prototype race cars. The M12 GT followed, based on the updated M12 racer, with big block Chevrolet V8 engines and monocoque chassis. Around four were built during the 1969-70 season. They were all originally open-top spyders, but at least one was converted into a coupe.
Were it not for the untimely death of founder Bruce McLaren in 1970, we could well have seen the M12 GT on the public roads vying for supremacy with Ferrari, Lamborghini and Porsche for contemporary supercar honours. If you can't quite afford the original, kit car maker UVA produced a homage to the M6 GT back in the late 1980s.