I mentioned this before, and I'm pretty certain that flipping the pickup and just wiring it back to front would be like turning the number "8" upside down. PLus it's the magnets inside that have to have the polarity reversed, so it would literally be the same pickup. I could be totally wrong mind. Think of the Dimarzio Crunch Lab for example, Petrucci uses it with the bar faceing both ways depending on the guitar.
Flipping the pickup and NOT wiring it back to front would have no effect.
Switching the Red and Black wires changes the phase relationship of the two pickups (whether or not you rotate the pickup).
With a "normal" humbucker, the screw coil has South polarity and the slug coil has North polarity (or the other way round, it doesn't really matter). Wired as a pair in the normal fashion, the two North coils are on the inside, facing each other and the two South coils are on the outside.
In this Ibanez wiring setup, we want the two inside coils to have
opposite polarity so they're hum-cancelling when both pickups are split. Rotating one pickup 180 degrees achieves this (magnetically), but doesn't change anything electrically - in position 2 on the switch you then have one inside coil active, and one outside coil active. To fix
that, you switch round the Red and Black wires.
Now, I'm OK with that, but....
I'm still not sure about the phase relationship thing, because as well as the magnetic polarity there's another factor, the direction each coil is wound on the pickup (think of a Strat set, the middle pickup is RW/RP - not just reverse polarity, but reverse wind too).
If the pickups do turn out to be out of phase, you
might need to turn the wiring of the bridge pickup "inside out"..... i.e. use Red and Black as the coil-split wires, Green as hot and White as ground (or vice versa). I think that would give the "reverse wind". But I'm not sure if it's necessary.
As I said, if I was doing this I'd use trial and error until I got it right. But I can't expect someone else to do that. :lol: