Just an update. I just did this mod today to my bros GS 300 (2006) and it works Great! I do get video and sound, hopefully it doesn't go out on him...
The only thing I would complain about doing this is that there wasn't much room to operate with the wires and the wires are very thin! Otherwise, took like an hour and 15 minutes cuz I took my sweet time not to mess anything up..