Modify system file

[JohnM]

This is not specifically related to a hackintosh but hopefully you may be able to help me.

I have (as well as a hackintosh) an old 2008 imac which has Catalina on it thanks to DosDudes patcher. I want to use bootcamp to install windows but I am prevented by the system being unable to find the optical drive. This is a known issue which can be overcome by modifying the bootcamp info.plist file, simply removing the "pre" from the usb boot line.

I have disabled SIP and run cmd  sudo mount -uw / and set permissions to read/write. Unfortunately I still get the error message "can't modify or delete sytem file because they are used by macOS"

Any ideas please?

[JohnM]

Just had a thought, I copied the bootcamp app to the desktop where it can be modified. I will post the result, although I am still curious to know if the system files can be modified.