Uhhhh, does he mean the motor that pumps the wiper fluid (that sprays the window) or the motor that runs the wiper itself?
The wiper motor itself is under the engine cowl cover. Remove the wipers, remove the cowl cover (remove a bunch of clips), and the motor & linkages will be exposed. 4 bolts removes both the motor and linkage, but both these items disconnect from each other at the motor itself.
Oh, and what do you mean by "center the wiper"? The right wiper will always move past the 90 degree straight-up position.
William
98 Civic + 03 Pilot