Nothing radically different, but assuming a regular Strat setup of three singlecoil pickups, a 5-way switch and the usual 1V/2T controls:
Position 1: Bridge
Position 2: Bridge + Middle
Position 3: Bridge + Neck
Position 4: Neck + Middle
Position 5: Neck
See, nothing major... just that position 3 is both the bridge and neck instead of the middle.
Cheers chaps and chapesses.