The soldering was as follows: From mobo L3B1 (north side) 5v, in to converter Input. From converter Output 3.3v, in to L5A1 (east side). From converter ground in and ground out (both) to the housing of the analog a/v module.

I removed the pin headers from the converter board. I fixed the converter to an empty space using gorilla double sided tape (thicker kind). You can hot glue or whatever you decide.