LOL OK;
Ideally,for practical purposes and production, the turning pivot of the wheel's suspension is above/at the center of the wheel.
This is zero scrub radius.
With a 700 wheel on a 140-1800E the center of the wheel is moved out 15mm.
40mm-25mm=15mm
This will increase track by 15mm+15mm or 30mm. IE Wider stance.
It also gives more steering 'feel' or feedback.
The downside is the wheels will tend to wander or trammline if the suspension is loose.
Virgo's are 15x6x20 et, so you have 20mm positive scrub.

I am not sure what you are referring to with the 'ES mags'
The alloy/steel cloverleaf wheels?
If they were supplied on the cars from Volvo then yes ET=40mm
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71-145-S