Are the shift knobs on the 05 w/ the captains chairs pretty generic? I mean Could I go buy an aftermarket one and it should fit?

Don't see why not. Most aftermarket knobs come with adapter spacers and set-screws.

Just unscrew it.

Completely generic, I twisted mine off to install my dash kit...currently looking for a replacement to match or something unique that I like

Check out the shift knobs here. They have a wide selection. They're all universal.

https://www.andysautosport.com/products.php?id=Ni02Xterra&make=Nissan&mcat=Interior&scat=Shift%20Knobs

I can get you this.

http://www.spaceheavy.com/art/armadabezel3.jpg
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Anyone, feel free to email me below.

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