If your going back to stnd, then just buy the correct stereo, as fitting a stnd stereo with different connectors will be a real pain, plus you have to get the connectors as well from a scrappy or breakers, then it may not work as their different stereos.
Try Ricky Smith on the IS200 facebook group, see if he would swap the stereos over for you with the correct one?
Also that black wire is the car aerial 12v power in connection.