I've put this video together as I couldn't find a good guide myself, and couldn't get an international firmware version, so got the EU LBT version and reflashed it over the international firmware.
When they are in stock, you can get these from Banggood here (affiliate link):
In the UK I picked one up from ElectronicWingman as I needed a few other bits from them:
I've set this out to be newbie friendly, so apologies if it all seems a bit too obvious in parts.
Amendum: This is an answer to a comment where someone said they only get the delete option when the highlight the firmware file. Make sure you update your OpenTX firmware :)
One thing I didn't mention as I figured everyone might be on the later radios now is the firmware running on your Taranis. To flash receivers, you'll need to be on OpenTX 2.1 (I thought it was just people like me that got the original batch that needed to think of it) Upgrading is a doddle, but if you are moving from a much earlier version you might need to change a few models as some of the mix sources might change (So I found some that should have been MAX were set to something else) but you can backup everything first. Go to / and download the OpenTX companion - this will let you backup your radio and upgrade the firmware then you can get going again :)
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