Does anyone know what wire im supposed to use for the remote wire for a amp install on the stock headunit?

 

it's the 'on' switch for your Amp if you have one installed. Three basic power connections to any amp (+), (-), and Remote. When the remote lead has power from the head unit (when the head unit is turned on) it tells the amp to switch on.

 

no i mean where am i supposed connect the remote wire in the back of the stock headunit like which wire to splice

 

There isn't a place...

I'd suggest just tapping into any wire that was 'live' when the car was turned on, but not live when the car was turned off...

Just check the stock connections with a multimeter, you should have 2 hot wires... 1 is hot all the time, the other only when the car is turned on... use that one for your remote... or you could use a toggle switch, but if you forget to turn the toggle off, your amp stays on

 

An even easier location is to tap into a fuse in the fuse panel. Find one that is hot only when the ignition is on (such as radio, wipers, cruise, etc....) Sure this isn't a true turn on from the radio itself, but how OFTEN do you drive the car with the radio off anyway?! And even if you do - it doesn't hurt your amp to be on with the radio off.