I've attached an image with some things circled. You'll have to remove the o2 sesor first, then the heat shield bolts, and that will expose the Exhaust Manifold to Head nuts. Mani to exhaust pipe bolts will be accessible from under the car

Also, I CANNOT STRESS THIS ENOUGH! Use a 6 point socket (NOT a 12 point) when removing the mani-head nuts. Trust me, you absolutely do not want to strip those nuts

 

I've found a seller on craigslist who has a 99-00 exhaust manifold (tubular) and said it will fit on my '96. He even said it will give me an extra couple hp because it's tubular. Is this correct?

 

It will not add HP.

Yes, it will "fit" however you'll have to extend one (if not both) of the o2 sensor wiring harnesses, as the locations are different between 96-98, and 99-00

 

When removing the o2 sensor, I have found that it is easier to just unplug it from the harness but leave it in the manifold. Then once the manifold is unbolted, remove the manifold from the engine bay, with the o2 sensor attached.

Then you can use a standard wrench and have plenty of leverage to get that o2 sensor off.

Then, install the o2 sensor in the new manifold while the manifold is not installed yet.

This works great if you don't have the special o2 socket and you don't have the cash to give the auto parts store $40 deposit to "rent" it.

 

Thats actually a great idea, good call.

 

what is a good offer for a manifold that has about 80k miles on it + installation? will i need a new gasket as well?