try "QTH CLassfields" or "Eham.net". Little bit of luck with QRZ, but they tend to price there stuff high.
I have a D-170 (non G) theres instructions online how to mod in an internal GPS board and a bluetooth receiver/transmitter if you're handy with. soldering Iron, PM me and I could probably dig them up. point being, dont be scared of the D-710A/E's - still a solid radio.