If you are not happy with the original TX range and you want to transmit on CB band (illegal with IC-7300 🙂 ) or if you (of course!) want to use CB to 2m transverter (this is legal) then you need to unlock TX to be able to transmit wider.
This mod is well described everywhere, so I publish my own pictures just to confirm that the mod is working.
Not a very big deal:
