Thanks to everyone here who mentioned Free-Way 6-position toggle switches. I used Free-Way's contact form, and the nice folks there made us a couple of wiring diagrams just for SE Swamp Ash Specials. (Free-Way's disclaimer is that these are "untested so far," and my SAS and new switch are still somewhere around my guitar tech's bench.)
Here's the Full Monty version. On the 6-way switch itself, you get the 5 Strat pickup options, plus the factory-original Bridge + Neck. It's factory B, B+N, and N on one pole, and B+Middle single-coil, Middle solo, and N+Middle on the other pole. Those last 2 are not stock:
But optionally, here we also rewire the stock Tone push-pull as as simple "McCarty" coil split for the 2 humbuckers. (Because why not?) That gives us 5 extra tones, for 11 total.
And why stop there? Inspired by some of Free-Way's existing schematics, we can optionally replace the Volume pot with a push-pull that puts the Middle pup in series with either or both outside pickups. That gives us 6 more tones (in combination with the Tone push-pull), for...17? On my other PRSi, I've had good luck with Alpha B500 linear-taper push-pulls as volume pots.
The diagram's fine-print legend says this schematic shows two resistors for partial coil splits, but you can omit those if you want full coil splits. PRS' own
SE SAS stock wiring diagram shows one 1.1KΩ resistor already onboard, so you'd need one more.
Finally, if you don't want to install a Volume push-pull for the series options, here's Free-Way's slightly simpler diagram, showing only the 6-way switch with the Tone pot repurposed as coil split. Happy modding!:
