The exhaust tubing is all the same on the coupes, spyders and gransports. not the same fitment, just the same bends and diameter as well as quality. the only difference is the Gransport comes with NO center resonator and the tubi back boxes.
Back boxes will be a direct fit, although you will need a skilled and motivated tech to hook up the butterfly operation.
contact Formula Dynamics as I understand they have some take offs for sale.
Robb