740 turbo front rotors

what is correct thickness? I have 285mm vented, approx 26mm width, they wont clear caliper carrier (zero clearance). I'm thinking I have the "jumbo" 940 rotors?

edit: jumbos they are & supposedly they fit late 1989 with ABS. Lesson learned

The jumbos started about 1991, before that big brakes they called them. The jumbos are thicker then the big brakes but the big brakes are bigger rotor 11.25 compared to 11 inch jumbos. They take different pads also.