The metro drive flanges used for metro vented brakes increase the front track by 12 mm per side. Just under an inch total front track width increase. This looks mean and fills guards but increases steering kick-back on single-wheel bumps.
To reduce the extra offset it is possible to machine one or two mm off of the face of the drive flange but no more. This could be done when machining off the castellations that get in the way of fitting many types of wheel. While you're there, machine off the excessive diameter of the drive flange.
It is NOT possible to use the standard mini drive flanges with vented discs because the brake rotor will not fit between the drive flange and the swivel hub. It MAY be possible to machine the mounting face of the brake rotor down sufficiently for the rotor to fit with the standard drive flanges because the rotor mounting face is about 15 mm thick. Doing this will require the caliper location to be corrected so that the disc is in the centre of the calliper. The problem then becomes the calliper clashing with the drive flange. Also, be careful with how much you machine because the mounting face needs sufficient threads left to secure the disc.
This photo shows machined metro drive flanges (standard width, just no castellations and reduced outside diameter) and metro vented discs. For Mokesta I have spaced the rotors and calipers 3 mm inboard so that the calipers clear the dished Sunraysia wheels. Spacers are laser cut.
M