I wanted to clarify how to remove the wire from the mount since I've been getting very PO'd trying to figure it out.
Identify the cable as it runs between the battery box and the engine.
Reach down with your left hand and grab it.
Turn the cable so that the two tabs that need to be compressed are sitting at 12 and 6, straight up and straight down.
Take a flat head screw driver and press down on the top tab while gently pulling back on the cable. ( Back meaning pull it towards the front of the car.)
Depressing the one tab allowed it to slip out partially and the bottom tab just folded all the way flat and the cable pulled out.
Honestly I could see this breaking the bottom tab on some brittle plastic so If you can fit some flat needle nose, regular needle nose will not fit, to compress both sides, that should work even better.
2003 Focus SVT - SOLD
2012 Focus SE Hatchback