Probably the main reason why they scrub is not because of the offset, but because they are too large for you use. The Hilux uses 205/70R15 and the 4x4 Extra Cab uses 255/70R15 stock. On an increase to 16 inch wheels for the former, something more appropriate would be 215/60R15 and the latter, 255/65R16. As it stands if you have anything but the 4x4 Extra Cab, the wheels/tires you are trying to fit are 12.52% larger in diameter... which is way beyond the recommended 3% limit. For the 4x4 Extra Cab, it is 3.33% larger which is still larger than the recommended limit, but shouldn't pose too much of a scrubbing issue but it can have more of an affect when combined with offset. So which model variant do you have?