Like most, I find the 9 switch positions with only 4 sounds wasteful and want to be rid of it! It seems easy enough to have one switch as a [Neck-Both-Bridge] and have the other switch switch between phase and out phase. This would only require a two way, so I need to use that final switch position. I love the dark tone of the Jag's rhythm circuit so I want to put that on the final switch position but I don't know if it's possible. And I don't really know what I'm doing.
I've had a go at making a wiring diagram which looks to me as if it might work. I took the bottom switch from a pickup selector mod, and attempted the top one myself- to do the phasing. In the mod I found, the black wires were grounded by an approximation of the green line, I don't know much about grounding so I don't what this connection would achieve. The purple lines are my attempt at creating the Jaguar's dark rhythm circuit sound, which would use equivalent resistors instead of pots. The Jag is in series, Mustang in parallel so it was hard for me to work out what was going on and created two problems:
1) In my circuit, two of each resistor and capacitor would be needed, for each wire of the parallel wiring- seems very wasteful and inefficient.
2) The Jaguar has a ground connection with a .01mfd capacitor (gets rid of the highs?) but if implemented on my circuit would it have that effect on all sounds, considering thoses purple wires are connected to the main wires all the time?

Maybe the purple circuit should connect to the vol pot, not the switch, so it wouldn't need the switch to be choosing the neck pickup.
I would love any advice as this is dominating my thoughts.