I got my JPac in today and its fantastic! The video quality is amazing compared to the old adapter I was using.
The problem is that Andy forgot to include the other 2 jumpers that allow you to select the control interface.

On the right side of the board there are 4 jumpers, 2 on the monitor Hz selections, and also 2 on the control type selection. It only came with the 2 on the monitor Hz selection jumpers, so I'm sitting with an awesome display and no way to tell the JPac what kind of control interface I am using. The JPac, when running on an arcade monitor, can work without the Hz jumpers attached, but with them taken off there is a slight annoying interference on the screen, thats why I would like separate control jumpers.
Does anyone know exactly what size jumpers those are and who sells them? I'm guessing that radio shack has jumpers, but that leaves me with the initial size question again.