For the most part the wiring of the jag-stang is identical to that of a Mustang.
The below schematic is a simple look at how the jag-stang is wired. The red lines represent the white wires you see when you open up your guitar.
Please Note: The pin layouts of the 3-position switches and the volume and tone pots are diagramed as if they were looked at from the top down. When you take your pickguard off and look at the switches from the bottom, the layout will be reversed.