Let me think on this. I'm sure we can come up with something. First some questions (just confirmation about what you're visualizing):
0 - the pickups are all single coils? Not two humbuckers on either end and a single in the middle?
1 - regarding these 5 pickup coils: The two on the bridge side are kinda paired together humbucker style? same with the two on the neck side? That took me a second to get, but I think that's what you mean - right?
2 - when you talk about tapping these coils, you're not actually tapping the pickups themselves, but the 'virtual' tap that would be there in a humbucker?
3 - the 5 way strat pickup selector switch selects between 'three' virtual pickups: the two paired together at the neck, the middle one, and the two paired together at the bridge? That is, you're looking for the following selections with the 5 way switch:
position 1 (neck): neck pair of coils, (hereby referred to as neck-pair

)
Position 2 : neck-pair+middle,
Position 3: middle,
Position 4: middle+bridge-pair,
Position 5 (bridge): bridge-pair.
Is that right?
4 - does the three way switch override the 5 way switch? For the first two positions, it's just doing the coil tap thing which should be no problem. But the third portion (
selecting a single (outer) coil untapped), do you require this to ignore the 5 way switch and just give you the full humbucker-type sound no matter what?
5 - and, this is just confirming the terminology: when I've been saying the word 'tapped' I imagine just one coil in a humbucker operational, with the other coil grounded. Here, 'untapped' would mean that both coils are active. Just confirming to make sure I am in alignment with your thoughts.