So I bought a 180 t-stat (my old one was stuck open anyway) and looked into my haynes to figure out how to put it in... and yeah, didn't know I had to flush the coolant! My apartment complex doesn't have a hose I can use, plus I've never done it before, kinda scared... Why DO you have to flush the coolant anyway? I don't get it

You don't have to...

siphon about 1/2 gallon of coolant out of the radiator and you are all set.

As stated, don't FLUSH the system, just empty some from the radiator.

Purpose: When you pull then t-stat housing off the LIM, coolant doesn't go all over the ground. Refill when done.

I just did this, coolant all over the ground lol. Just wondering though what do you use to take coolant out of the rad?

could one just undo the lower radiator hose and just let it run into a container or something?

There should be a drain plug on the driver'* side of the radiator towards the bottom, accessible through a hole on the back side of the radiator.

That'* a LOT messier to empty from the bottom. Go to the hardware store and get like 6' of 1/2" diameter clear tubing, save an old milk jug or other suitable container and go to town. VERY easy to do

what he said... alot easier.

So after it is changed should I notice the car running cooler on the guage?

Yes, a 180 will open at 180, keeping the engine running cooler.

Air still must be flowing through the radiator though, so sitting in traffic on a hot summer day will still cause your temps to go above 200.