2015 silverado radio frequencies

[Kiwi]

I am currently in new Zealand and have a2015 silverado with nav radio, i need to reprogram radio tuner to UL8 frequencies to pick up radio stations, I have previously done this with SPS , but as of 2014 there is no option to change frquencies on a USA nav radio. Is there any way around this, Can it be done using VCI programming, Is there an export radio that will swap.

 

Thanks Kiwi.