DISCLAIMER.
You perform all the mods shown in this video at your own risk. I anm not responsible if you brick your radio. (Unlikely)

This is not a definitive how to, but how it worked for me.
Included is where to get a programming cable, where to get the firmware files and how to upload to your Quansheng UV-K5
This should also work for K5(8) & K6

I got the cable (that works for me) from Ebay seller g0oyq-steve. I am not affiliated in any way with this seller. But his cable works for me.

For the firmware files, I use the files section of the Facebook Group "Quansheng UV-K5 UK Users"

The interface I use is the Web based UVMOD site.

You will need Chrome browser. I couldn't get it to work with Edge or Firefox.

UVMOD is at...

who's matt.github.io/uvmod/index.html