Thanks. Someone told me they used a rechargeable battery and were all sealed up. Having watched your video I've taken mine apart and its similar to yours. Result.
Ah, this looks so easy. I wish I had seen this! I watched another video, with a ford s max key fob, and have prised the whole top open, instead of the bit shown on.the video above! 🙈 It won't click back on. Any ideas? Thanks.