3800 Supercharged series iii in 99 grand prix

Woould it be possible to pop a series iii into a 99 grand prix? and obviously dimension wise, but electrically? would I gain any HP over my current 3800 non s/c other than the difference in mileage on the motor and the s/c? Also will the big 5 spoke rims from an 04+ fit on a 99?

Yes to everything. Only trick will be switching to an l32 map sensor, you need to get the male plug from an l32 harness and you'll need to get a tb adapter to run your tb

With lots of swaping of parts and some custom plates to make the throttle body work with a L67 throttle body that you would need because 04+ (series 3) are drive by wire.