Garmin Edge 1000 replacement back

Has anyone had experience of changing the back of their Garmin Edge 1000? My (four years old) one ‘froze’ inexplicably and wouldn’t turn off using the on/off button at the side. After multiple attempts without success, annoyingly, the plastic  case surrounding the button cracked and fell away. This seems to be a known problem judging by the replacement parts available on eBay. I’ve managed to open the device and separate the front from the back. The minuscule connectors disconnect and reconnect quite easily so I’m pretty confident that a second hand replacement back will bring the device back to life again. Garmin offer a replacement unit ( new screen and back but not the electronics) for £190. Alternatively I could go down the eBay route with a used back from China for about £30.  Anyone tried this and was it successful?

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