Just cover your battery, alternator, and air filter and clean away. Also I wouldn't directly spray it on the cops either but it wont hurt them, if you are going to do it think of it this way, use the water just to rinse it off not power wash anything off. If something is stuck on there use a good degrease and a brush, then just rinse it away.
Also before you start that engine afterwards I would let it dry off a little and I would blow out the spark plug holes.
2000 GT 5 speed
SCT Brenspeed tune, subframe connectors, Elbach springs, Steeda shifter, Spec clutch, Spec flywheel, 3:73 gears, A/C delete, CAI, BBK headers, H-pipe, Flowmaster catback