The first Infiniti Performance Line offering was unveiled at Pebble Beach last month in the form of the IPL G37 Coupe. The 348-horsepower G hardtop wears a factory-designed bodykit and came with engine and chassis tweaks to make things slightly firmer and faster. It goes on sale in December.This week, its droptop brother will arrive at the Paris Motor Show. Infiniti hasn’t announced power output,