Yes, they are 16x8" & 16x10".
Here is a photo showing Geof's rear dish.
I reckon Cobra's look good with front wheels under the front guards, but the rear wheels look great filling right out the rear guards, as long as it doesn't cause rubbing etc.
So at the moment it does look like Geof's could have specified more front space(less backspace) on the rear, but he has gone for a bit of insurance with his offsets, which is never a bad idea.