Remove resistor: R1396, R1400, R1402 on the main unit of the radio. 

Press and hold down the "MHZ" and "REV" buttons on the front panel
of the radio, while powering on the radio. 

Modification is complete. 

New frequency:
VHF RX 108 - 180 MHz
VHF TX 136 - 174 MHz
UHF RX 320 - 999 MHz
UHF TX 410 - 470 MHz