going back to the Alloy rear hubs, the distance between the centreline of the axle and the Lower outer hingepin on the arm is actually greater than the standard hub.
the standard hub has a 13.5mm gap
the alloy is 15mm gap.
talking to Phil Booth the change had improved steering when lowering that outer hingepin closer to the wheel
The E.C car has changed offset, the hingepins sit deeper inside the wheels, as close to the wheel centreline as possible, to reduce the jacking effect caused by castor. This is said to be quite an improvement, requiring the wider arm spacing on the chassis and thinner wheel hexes to maintain track width.
Im not sure if the height of the outer pin attachment point on the new rear hubs has changed again.