Are you replacing the whole waterpump+housing or just the waterpump?
If you're just replacing the waterpump...my mechanic replaced the waterpump (only) twice. Each time it started leaking again after a week or so. The 3rd time, I told him to get the Motorcraft waterpump+housing assembly and use that (I paid the difference, as the waterpump+housing is more expensive than just the waterpump). No leaks, and that was about a year ago.
