Edit info.plist to make bootable USB Running OSX El Capitan 10.11.6 and trying to make a bootable USB for windows 7 bootcamp on my MacBook Pro. I disabled the SIP by using Terminal in Recovery Mode but I still cannot replace or edit the info.plist file. Optical drive is broken so that's not an option. Any advice appreciated!
It is pointless to solve your problem. If you succeed in creating the USB Windows installer, you probably will not be able to boot from the installer on your Mac. You are suppose to use the optical (DVD) drive. 

There are alternative methods to install Windows 7 on your Mac. For example, see the question: Boot camp install of Windows 7 issue, no bootable devices.