Nexus 7 does not show under 'adb devices' with Windows 8 PC

I have done this in the past a few times, I see this process has changed a little.

Yes, I have already:

• Installed Android Studio
• Changed the USB computer connection to the NOT-very-straight-forward option Camera (PTP).
• I have tapped the Build number found under Settings->About tablet 7 times in anxiety until I "became a developer" and the good old {} Developer options gracefully appeared again under Settings->System section.
• Inside Settings->Developer options I have upper Developer options switched ON, and USB debugging as well.
• On Android Studio, Tools->Android->SDK Manager I have installed Google USB Driver rev 1.0
• Made sure both USB cable and ports and Nexus 7 are working and %100 functional. (I can copy the pictures from the device to the PC just fine)

EDIT: Where are the Nexus 7 (2013) drivers for Windows 8.1 available at?

What did I miss? Besides the fact I want to to get this done, I'm also partly posting this question so other developers who want to test on their 2nd generation Nexus 7 with Android KitKat 4.4.3 would have 1 complete thread with all of the instructions found here and there because this isn't as straight forward anymore in my opinion.

I have finally figured this one out:

This guide tells you to go and get the Google USB Driver from google.

For me, Downloading it as an optional SDK component just didn't do the trick. But on the very same page, there's a button that says Download Google USB Driver (near upper left corner, in blue.) This gets you latest_usb_driver_windows.zip file.

Use this guide right here If you are unsure how to install this driver. I could see my Nexus on adb after I've done this. Best of luck!