I don't have that radio, so take this with a grain of salt. But here you go:
If it's totally flat, with what looks like printed circuit board copper traces embedded in it, the terminations typically have a compression latch that's released by sliding up a little lip at the top of the connector. Finger nail works if you can get to it, or a pick, or small screwdriver. It will only move up less than the height of the connector.
If it's not that kind of ribbon cable, then never mind....
Charlie