Remove fuse and do without?

According to the manual. All I have to do is make sure that the starter switch is at the position '0' and switch off the electrical circuit before removing a fuse.

Easier to just remove the key, but I want to double check, as I plan to remove the fuse for the radio, do the latter part mean to imply making sure the radio is turned off before I remove the fuse? Or do the manual meant to imply removing the battery lead before removing the fuse?

Also manual shows that fuse number 12 and fuse number 27 are for audio system (fuse 12 says audio system, vehicle battery power feed). I assume to make the radio/CD non-operational, I have to remove both fuses?

Am I correct? Just wanted to check before I remove the fuse.

disabled my radio / cd player as i use another system
i simply pulled the two fuses out ( ignition and radio both 'off' )
didn't have any issues after ..
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