I ordered the part I needed from Amazon for $24.80.
http://i.imgur.com/HG2Z6lo.jpg
80% of the battle was finding where to put it. Everything I searched on kept directing me to the radiator drain plug at the bottom of the radiator. But after much searching I found it on the engine block. This picture is post-install. It's at the center of the picture (the orange thing in the darkness)
http://i.imgur.com/6nJWcDv.jpg
This is a closer picture. The orange piece with the wire running in.
http://i.imgur.com/tWDme7C.jpg
Everything I read suggested that I flush the radiator (through the normal radiator drain) to get the part in. I did this. But then when I unscrewed the plug from the engine block even more coolant came out. I'm not sure if draining from the normal drain helped at all. I probably should have just let it drain from the engine plug even though the engine kept it from flowing straight into the drain pan I set up on the floor. The plug was VERY tight and hard to reach. I had to use a monster ratchet with an extension or two. 1/2" to remove and 1" to fit the new plug.
http://i.imgur.com/gGAgjzl.jpg
I zip-tied the power cord to the a/c overflow pipe to keep it away from hot engine parts and then threaded it through the lower (and unblocked grill).
http://i.imgur.com/BKThCsF.jpg
http://i.imgur.com/wRiLqBL.jpg
My air dam was a pain to put on and I didn't want to take it off for this install. I used my dad's floorjack while I was looking around for the plug. After I found it I realized I didn't really need to get under the car at all.
I haven't used the heater yet, but I'll try it tomorrow morning and see how it goes.