Many of the parts will probably filter down to the mainstream car when the newly designed MY 2015 cars come out.
Some already have, like in the Track Pack.
I wouldn't be surprised to see the cams and a version of the intake (minus the Boss logo) make it into the GT at some point. Probably not the heads due to the time/cost of CNCing them nor the pistons because of noise conserns.
As the Dodo bird did...lol
And I agree with previous posts, part of the over all package will filter to the GT but hopefully not the entire engine because that is what makes the BOSS so special!