Fixing In Place
Started by cutting down the main power board using the dremel and hot gluing it in place.
Wiring It Up
Wired up the harness to connect the VGA convertor board to the TTL RGB output of the BBC. The hooks will be connected to the resistors on the inside of the board. This means that I don't have to solder the entire lot to the board.
Just need to trim down the board using the Dremel.
Sorted out the power switch which will allow me to switch between the external power and battery.
Next job is to wire up the internal power to all of the above items.