The write-protect switch on an SD card doesn't connect to any internal electronics, so it must just be respected by the software controlling the card reader.
Is there any way for me to override this setting and mount a write-protected card with read-write permissions?
Not likely. The read/write access is set by the drive's firmware and is usually impossible to change.
Yes you can overide. on one side of ther SD_card there is a small nik ( remember cassette tapes ). if you cover this with some thin card (selotape works too, but needs several layers ). then it will allow the transfer of music pictures etc, onto the protected sd-card.