I have a new Galaxy Nexus LTE (cdma) that I am wanting to update to 4.0.4 and better radios. I have no idea what to do. Please steer me in the right direction.
Well, you will need to unlock the bootloader first. This will erase everything on your phone, including whats on the sd card, so you'll have to back that stuff up if you want to keep it.
Next, you will root the device. There are stickies in this subforum posted up top - they will guide you through unlocking the bootloader and obtaining root access.
Next, You will need to flash recovery - this can be done with rom manager app, or manually in adb. Judging from where you're at, probably need rom manager app after you have root.
There is a sticky up top by Cyber Warrior on how to backup, and flash roms. You should read this as well, it will teach you how to make nandroid backups in recovery mode and how to flash roms correctly in recovery mode.
The first thing you want to do, after you have root and ahve flashed recovery mode, is make a nandroid backup. This will be your safety net, in case anything goes wrong when you flash something.
It is advised that, before you flash a rom or a mod or kernel or whatever, make a backup that works because it will save you lots of trouble if something gets wacky.
After all this, you are going to download the 4.04 radios and bootloaders (an easy way to do this is with patient zero's get ready package) - and flash in recovery mode.
Next, pick a rom and enjoy.
Any questions feel free to ask.