One more post on water pump
 

Hey guys, I decided to replace my water pump, but i want to know if I should replace the housing too or replacing the pump will be fine (my car has 166K) The difference in price between them is 100 bucks....

All you need to do is replace the pump and the gasket. Change all your belts while your at it.

Unless the housing is leaking near the thermostat opening (or along the block), you should be fine reusing it.

Also change hoses while you're at it.

PaulC

Just ordered a new pump, 50 bucks