Neither have the resources nor the time to do this myself but I have a product idea I can assure you would sell. Mainly because I get at least 3 pm's a month about it.
I and another member previously made a handful if brackets to fit z32 calipers to wrx's using LGT rotors and they fit under 16 inch wheels. You can buy loaded z32 calipers for painfully cheap and they are identical in every way save the mounting ear location (ie the spacing is the same) and you can even find aluminum calipers very easily. I am more than willing to supply you with z32 calipers if you are interested in making a QUALITY/safe bracket. The reason I never ran the setup was because I went to USAF BMT and I was not a fan of the thin bracket design.
Please pm me.