Granted, but I bet there are enough differences that it wouldn't be just a bolt in. I would also be a little concerned with the programming in the pcm as I'm sure there are differences between the two cars just based on the fact that they are for different countries with different regulations.
It probably wouldn't make that much difference, but I wouldn't buy it until it had been actually installed and tested on an american G8.
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Kinda sorta, yeah, no?
'02 Black GTP - RIP 03/03/08 ||| '06 Black G35 MT6 - Stock ||| '73 Chevy half ton(resurrected)