The Nissan Path

I am planning on dealing with the oil leak coming from my drivers side valve cover in the near future. Obviously I am going to have to remove the upper air intake plenum to do so.

Looking for any tips on doing this, things I could OR should do while I've got it apart. Do's and don'ts.

I figured while I have the intake off I would relocate the knock sensor from its factory location.
Clean or replace my EGR
Replace the leaky idle control thermo unit.

Should I use factory gaskets?
Remove the throttle body and clean the intake?

Your input is appreciated.

If the knock sensor isn't giving you any problems, there is no need to relocate it. Besides, you'll have to remove the lower intake manifold to get to the knock sensor and you don't need to remove the manifold or upper plenum to do the relocation, anyway. You get a knock sensor and subharness for a 95 Maxima and splice it into the engine wire harness. There are videos on YouTube showing how to do this. But, like I said, if it isn't broken, don't fix it!
Removal of the upper plenum is pretty straightforward. The biggest challenge is disconnecting and reconnecting the coolant hoses at the back of the intake plenum (there's not a lot of room to work with). The other issue is that sometimes the EGR passage tube gets rusted to the EGR valve and will snap the threaded end of the EGR valve off, causing one to need a new EGR valve and passage tube.
You don't need to remove the throttle body, but cleaning it is a good idea. Just spray it with some throttle body cleaner.
Nissan gaskets are good. I stick with Felpro gaskets on the aftermarket.