Make sure your motor is cold, cover your filter and your alternator, Simple Green the living piss out of the entire engine bay, let it sit, spray on some more if needed, and then rinse it off (avoid direct jets of water, use a nice nozzle that lightly sprays the water)
I've done that to a 97 GTP, my Lumina, my Cutlass, and the TGP with no problems. Just make sure you cover up those 2 things and you'll be set.