1. Remove the battery.
  2. Remove the antenna and pull off the top dial knobs
  3. Remove the two screws on the back.
  4. Unlatch the rubber ports cover from the post on the back. Use a small screwdriver to slip under and it just pops off.
  5. Pull the case up and off.
  6. Detach the rubber button cover from the front and set it aside.

At the bottom front of the circuit board, below the number button pads, there is a small diode labeled D729. Remove that diode shown in this pic:

Remove the screw that holds the LCD display in place and gently lay it over. Underneath the display there is a row with three diodes labeled 1,2,3 near the speaker ribbon cable.

Remove diode D730 (labeled 1) 

This is how the 3 diodes should be after mod:

1 – removed
2 – removed (USA version does not have it)
3 – must remain in it´s place (that means DO NOT remove it!)

Reassemble the radio and perform a FULL reset by going into the Auxilliary menu.

Transmit range is now:
136-173.995 MHZ
410-469.975 MHZ

note: Thanks to XE1BRX for updating the original version of this mod resulting in greater TX frequency range.