One would simply need to determine if the longblocks (including valvetrain) are identical between the three engines. I'm assuming they are not, but it is possible that the are. If they are, you would need to obviously pick up the supercharger, intercooler, intake piping, mass air meter, and ecu (you could probably flash the oem supercharged calibration to it, but often times it's not the same ecu. The ECU (if new) would need paired to your instrument cluster and possibly your keys as well. This is all best case scenario. The most likely case is that brp uses a lighter (and weaker) rotating assembly in the naturally aspirated engine models to improve throttle response, increase power, and reduce cost. It is also probable that the camshafts and valvetrain is different as the n/a engines do not rev as high.
Attempting to supercharge the engine that was not designed to be supercharged by the OEM is absolutely possible, however, you will see a serious reduction in engine life. Most likely catastrophic failure of a piston, rings, or connecting rod. It is possible to have the engine live a long life in some over engineered applications but you need to be very careful with the setup. Nothing can be on the ragged edge of it's duty cycle. I'll list some things to consider: Fuel pump and fuel injectors. You do not want to exceed 80% duty cycle at max rpm. Short block. Most of the time the connecting rods and even pistons are up to the task of handling more power than what they are do in stock form provided you don't see the slightest bit of detonation (pre-ignition). This will eat even the strongest rotating assemblies apart. Mass air meter: The mass air meter must not reach it's maximum voltage at any time, in any weather. If it does, you will most likely see catastrophic engine failure. Valve springs: If they are not the same as the OEM supercharged versions, you are playing with fire if you increase the engine rpm into the 8000's.
It can be done. Anything can be done. It may be easy, it may not be. You're first step should be comparing part numbers for the crankshaft, connecting rods, pistons, rings, camshafts, valve springs, intake manifold, engine block, fuel injectors, fuel pump, and ECU. If those are a match, it's a walk in the park. If not, I do not recommend it. It will cost a pretty penny, and you'll probably worry about pushing it too hard (and you should) to enjoy it. If you do hurt it, and you will eventually, your wallet will get even lighter.
