My first attempt to flash the titan radio onto the vogue was by changing the device id, which was unsuccessful, but it displayed the radio version, and other info red during boot, but would just hang. After removing the spl from the radio rom, I was able to boot with the new radio successfully, although now it displays no radio, in red or blank info at the bottom of the screen. The option to enable rev-a is also missing, which is being discussed in the titan forum
http://forum.ppcgeeks.com/showthread.php?t=20905.
So I began looking into spl.nb file with a hex editor it seems spl.nb, might be the key to getting gps and rev a, on the vogue. If someone is more comfortable with a Hex editor have a look at it.