[san rensho]

I would replace the WP right away. Most consider it a maintenance item that should be replaced every 5 years or so before it fails, because when it fails, the plastic impeller usually disintegrates and the plastic pieces can clog the water passages in the head and lead to a cracked head. While you are at it, change the motor mount. Its inexpensive, almost always fails at your mileage and disconnecting the coolant hoses makes changing the mount a breeze and lowering the engine slightly while replacing the mount makes replacing the WP a breeze.

Don't reuse the coolant, and don't over-think it too much, just get the Porsche stuff, its expensive, but you are not going to be changing it anytime soon.

As far as bleeding the coolant of air, the Pelican method has worked fine for me on 3 occasions. after you have bled the system, go to a multi level parking lot and stop for few seconds while going DOWN a steep ramp and rev the motor a bit to get any air trapped in the rads out.

I would wait until the overflow tank fails before replacing it. Just pull up the carpet in the trunk and see if there is any coolant leaking. If its dry, wait. Its a pain in the butt to replace. I still have scars on my hands from replacing mine.