Coolant Flush? 2K Stang

[StangVert00]

Greetings,
I think it's time to change the coolant on my 2k 'Stang GT Vert. It's probably browner than "Dirt". It have never been done before.

My questions are these:
Where is the release valve to release all of the coolant?
and second:
Do I have to "recycle" the old coolant like I have to do with motor oil?

Thanks in advance,

StangVert00