Windows install from DVD or USB on El Captain
Reboot into Recovery Mode by pressing Command+R while the MacBook starts.
Navigate to Utilities and then Terminal.
Enter csrutil disable ; reboot which will disable System Integrity Protection (SIP) and restart the MacBook (Disabling SIP will allow us to replace the original Info.plist with the modified one).
Once booted back to normal mode, enter mv Desktop/Info.plist /Applications/Utilities/Boot\ Camp\ Assistant.app/Contents/ in Terminal to replace the old Info.plist with the modified one.
Reboot the machine back into Recovery Mode again (using Command+R).
Enable SIP using csrutil enable ; reboot.
All finished! Once Boot Camp Assistant launches again, the option “Create a Windows 7 or later version install disk” will appear.