1) yes tuner can do that based of the exhaust manifold sensor as well as your wideband - once you feed the signal back into the ECU.
2) AEM offers a 30 dollar or so kit to drill your own bung into the exhaust. Its a slip on device with no welding:
http://www.aemelectronics.com/produc...-sensor-mounts
I personally would get one welded.