The knock sensors (there are two of them) are located under the intake manifold. It shouldn't be a tough swap for you. The only specialty tool you'll need is a fuel line disconnect tool, and one can be had for just a couple of dollars.
On each of the fuel injectors is a tab that you'll lightly pull to unlock the clipping mechanism. Squeeze the now-exposed tab on the body of the injector connector until it clicks and lightly pull the connector from the injector. Repeat for the remaining 7.
Loosen each of the ten 10mm intake manifold bolts to the point that you can lift them up. They won't pull completely free of the manifold, so don't worry when they won't come out.
Disconnect the miscellaneous sensors that are on the manifold, and lift it out and to the side. You'll see the wires running to the two "pods" under the intake manifold. Since you're there, might as well replace both simultaneously.
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