Here is the temp gauge I picked up from the store. You can make the bulb shine different colors by placing a rubber filter on it so that's nifty. The mechanical line is really soft and you can bend it really easy. I know the older ones were pretty hard to bend and felt fragile. Twenty bucks.... what else can I say?
Here is the only tool you need besides a wrench to install this gauge. Luckily it was exactly the same size as the nut that secures the sensor to the water passage adapter. Nice and easy.
And now I have a nice big hole to put the sensor through. The gauge came with a rubber grommet to seal the hole around the hard line so that can be installed as well.