Thanks Cobber! One problem, i've just realised that i only have the AU 'Sensis' splash version which differs slightly from the US/EU standard vanilla Garmin one. Does anybody have a 250W logo from an EU or NA hwid 0737 to compare?

As far as converting to 465T, firstly just check your PCB P/N. It will almost certainly be one of these, but we need to be sure: 105-01375-00, 105-01375-01, 105-01375-02, 105-01375-06, 105-01392-00, 105-01392-01 or 105-01392-03. On the 'Where To?/View Map' screen, hold the battery symbol for ~5-6 seconds, you get a page with 'SW Ver' in top LH corner, press next and check the PCB P/N which show directly beneath 'Version Information' at the top.