The way I see it, or if I get it right, you want to bridge the the 4 ch amp to get the most power, and have the midbass, mid and tweeter somehow all connected in parallel or series to get a correct load, while using caps to protect or limit the range of frequencies sent to a them?
Or use 2 ch for the mid bass and the other 2 ch for mids and tweeters?
I'm not skilled to determine the cap and coil values needed or create a passive crossover for such drivers, you most know what you are doing. You have an HU capable of active pre amplified frequency filtering that will offer clean sound and I simply would not deal with passives or caps if it was me.
I don't want to steer you away from your plans, I know sometimes you just have to try to see how it works and make changes or eliminate drivers if the result is not good or it can be better. I'm just sharing my thoughts, here, feel free to keep reading or ignore my suggestions. :act030:
A 3 way passive system will be very hard to tune specially if you have at least 2 drivers connected in parallel with different impedances and sensitivities and passive post amplified frequency filtering, not having an extra 2 channels to have full independent output level control to balance their sound. Tweeters and mids need to be next to each other, the closer the better as you probably already know.
Also if you keep the tweeters and mids near the dash or A pillar, you do not need extra new wire for extra speakers in the doors or window sail panel. Just run wire to the dash, some fabrication or special mounts will be needed for the pillars, but it may be way easier than drilling extra holes in the door for extra wires, or placing the caps coils or passive crossovers somewhere in the door panel if no extra wire is fished there for bi amping drivers. Many other places available to place caps coils or passive crossovers in the dash, behind glove box, kick panels and more.
Also A pillar mounting for mids and tweeters will give you a better stage besides making things easier, tweeters on axis or off axis will depend on on where they sound better without being harsh, you have a very powerful sound processor in the pioneer HU you can lower the output levels and EQ as needed.
I assume the 6.5" silver flutes will be driven alone with 2 channels, if not I recommend it since those are the ones you will time align and if they are connected in parallel or series with other drivers, you will not get the full potential from them.
If you are using the 8" silver flutes, I then would understand the need for 3" drivers.
Honestly the 6.5" flutes play good and flat up to 3200hz, even a gap between 3khz and 3.5khz is not significant . I checked your tweeters minimum response of 3500hz, and you can simply EQ that gap, or bring the HP on the tweeters to 3200hz, I'm sure it won't hurt them.
If you ran your tweeters, with the pioneer HU, you will need to set the HP at around 3200-3500hz, to off/ open or 20khz or higher LP if they can play higher, then the silver flutes with the other 2 channels from at 80 HP to 3000-3300hz LP wherever they sound better, no caps no coils no passives connected to the flutes.
For protection if it makes you feel better, a 12uf non polarized polypropylene Cap, the value based is aprox on half of the low crossover point of the tweeters, and it's 8 ohm impedance, connected in series . 11.5uf would be more accurate as you would find out if you double check it with an on line calculator, this is just to prevent DC voltage from the amp, even if the HU, looses power or the battery dies, the HU should no loose the tweeter crossing setting ever, but you will never know, if your amp pops or thumps when you switch your key, it can damage the tweeters.
And the cap will not interfere with the pioneer's digital crossover since it's frequency cut off will be below the pioneers crossover point.
This is how is done today, I'm sure I would not be the only person not in favor of a 3 way passive when you already have drivers that can play in that range and have the processing to do it.
If you want freq from 1k-4khz to be crisp and smooth, there are 2-3" wide band drivers that play up to 17-18khz if more detailed sound is expected with a raised in your face stage.
Again long post a lot to read and think about. :act063: