transmission swapping

It will bolt in. The electronics MAY be the same and work in the older car. (Make sure though before you start) However the transmission will not be the heave duty version that was used with the supercharged cars and will not stand up to the higher horsepower and torque unless driven gently. While they're not plentiful, it shouldn't be too hard to find a used one that will last the rest of the car's life. May not have to be out of a GTP. There's a couple of other supercharged GM cars that used the same one. I believe the one I swapped into my '03 came out of a Buick Roadmaster.