Running on a very tight schedule so no time to get an on/on/on toggle... what I have is a guitar with two P90 pickups with one volume and one tone, and a 3-way mini toggle (SPDT on/off/on) for pickup selecting. I've tried wiring each pickup to each side of the toggle and the centre to the volume pot but it's dead when in the middle position, I'm assuming as it's on OFF on. I have read that there are ways to make this work but no explanation of how.

Is this possible? Does anyone have any diagrams?
I don't see how this could work with a SPDT on/off/on since the only way you could use both pickups at once is to add a jumper and having the bridge and neck work together in 2 positions.