How do you install a water pump in a 1995 Johnson 150 hp outboard?

To install a water pump in a 1995 Johnson 150 hp outboard, first, remove the lower unit by disconnecting the shift linkage and unbolting the lower unit from the powerhead. Next, take off the water pump housing by removing the screws and then extract the old impeller and housing. Install the new impeller and housing, ensuring the impeller is properly seated and lubricated. Finally, reassemble the lower unit, reconnect the shift linkage, and test the pump to ensure it's functioning correctly.