If it is easier for you, you can just break the 6th pin at the AV connector. Simply count to the 6th pin, prop it up with a finely pointed tool such as an exacto knife until it protudes from the grooves. Get some needle nose pliers and turn and tug at it till it breaks. You might need to cut some of the plastic off of the AV connector housing to get in and get a clean break, but that isn't a big deal, it will still seat snug in the DC's AV port. Just make sure you count correctly and from the correct side so that you have the right pin. Otherwise it is bye bye VGA cable/box.
For the VGA breakout, you will need a multimeter to perform a continuity test to find H and V sync. Here is the pin out:
http://www.gamesx.com/hwb/ca_9to15VGA.htmlIf you don't have a mulitmeter, you can buy a VGA to 5 bnc cable. R,G,B,H sync, and V sync are all already color coded for you. And the shielding from any of the wires can be used as ground. This route is slightly more expensive as the VGA to 5 BNC cable cost anywhere from $7-$40 if you don't have one already.