brake wire location for after market Radio

My car is a 2002 ML320, USA Spec, Non-Bose.
Can someone advise which of the 6 wires is the parking brake input is the one I should tap into or if there is some other location where i can pick this up?
I've read through other installs but can't find one where any one has connected to the parking brake.
On a side note, I've ordered the JVC KWV-660BT ,
https://www.crutchfield.com/p_105KWV...KW-V660BT.html
but like the Boss BE7ACP better:
https://www.crutchfield.com/p_104BE7...C-Package.html
So not sure which to keep, have a few days to decide before I receive package.
TIA,
Maneesh

Will go look for this ahead of time. Although I find it confusing the need for the radio to connect to the parking brake and not the regular brake. Will check out other installations to confirm, even though the instructions specify parking brake switch.
A hundred thanks to you for being one of those individuals who keep this forum alive.
Cheers,
Maneesh
Otherwise if its a JVC/Kenwood just ground the light green wire and dont worry about the parking brake.


