So, I have a Squire strat that I've been testing some wiring mod ideas on and it's in a weird pickup configuration (originally sss, but the bridge pickup was removed because I never used it and I like the sound it has) and what I want to do is when it's in the bridge position of the 5-way selector, it combines the neck and middle pickup and engages a treble boost circuit. I have an ok idea of how to combine the pickups (I think) but I have a hard time visualizing it on the stock budget switch it comes with and I have no idea how to, or if I even can have it engage a treble boost circuit without some other switch. Any advice or diagrams to do this would be greatly appreciated.
For reference, here's the pickup configuration I'm talking about.