Please help with wiring moded Fender Jaguar.

I can't but give it some time. Others may chime in.

 

If these are single coil pickups your idea for Single/Off/Parallel for each pup is not possible. Also the Out of Phase idea on a bass is questionable. What pickups are you using? And why the Phase wiring, which generally cuts low end?

 

If they are to all be single-coil, wire it like a Strat and you can use a phase switch to keep any 2 pickups in phase. If 2 are to be humbuckers (splittable) then you can use the Single/Off/Parallel switching on those. But that's a more complicated wiring, and you can use a diagram for 2 splittable humbuckers, just adding another single-coil (pos wires to the phase switch).
Search 'Cadfael's'.

 

Maybe a diagram of the squier bass vi will help with your on off switches. I'm no expert but from what I've read the series parallel switch wont function once you get to 3 pups. You could keep the series parallel for your normal J pups, and wire the third pickup in parallel to those 2. I know nothing of phase except that I hit the phase switch on my carvin for stereo!
Best of luck my jag playing bruthah. Make sure you post pics to the Jag bass club forum when you're done!

 

It can be done with three dpdt switches and a 4pdt switch go from series to parallel. Or a Fender S1 switch.
It would be the same as Brian May's guitar wiring.
If you are using toggle switches, make one a on-on-on like Dan Armstrong SuperStrat and your set.

 

a few years ago I wired a custom stat with 2 rotary switches. one was a 6-way pickup selector (the extra position was for neck & bridge together), the other rotary switch was a master series/parallel that only worked on paired coils. iow, pos 2,4 & 6. if memory serves, you need 4-pole switches, but it sounds pretty close to what you are wanting. plus this gives a very simple functionality.

 

if you don't like rotary switches, yeah a super strat switch will work just the same but it's more expensive and only has 5 positions I believe.

and a fender s1 would work as the series-parallel...