redruM69
Your UnitID belongs to a nuvi 760 device, so you should use HWID=754 firmware, I think.

Quote Originally Posted by redruM69 View Post
I CAN get into pre-boot usb mode, flash with updater.exe, but it never gets past "Loader Loading" and is stuck in this loop.
Can you please clarify this?
If you flash the original HWID=754 firmware with updater.exe, what happens? Does it show "system software missing"? Or does it boot and then show "LOADER LOADING ..." and hang? In the first case it's likely that the flash chip is broken. In the second it looks like the GCD file is corrupt. Then using GarminCure3 to get into the mass storage mode and remove the GCD.