I'm trying to find some dual-humbucker schematics, but none of them quite seem to match what you've got. What is the 2-way switch? You seem unsure that it even is a switch. Have you never used it?

Here's some links I could find that seem relevant:

http://guitarelectronics.zoovy.com/product/WDUHH3T1101 (seems to be wired as a single-coil)
http://users.chariot.net.au/~gmarts/pix/sd_hum.gif (has volume and tone for each pickup)

Oh, wait. Here you go. Seymour-Duncan's schematic for what you have. There's also one that includes a separate switch. Here's a link to all of their schematics.