68 Camaro rear seat transplant question

[colorado80439]

I looking to transplant a late model rear seat in to a 68 camaro, it's from a '14 lexus is 250 f sport, wondering if i should form the seat cushion to the Camaro or cut the floor pan out of the lexus and fit it to the camaro. seat dimenions are very close if not the same in length and width
Thanks Dave