rear disc brakes on 8 3/4

Buschi340 said
what Kind of Toyota? model or part number? and how modified?

Ford Cobra is a simple new Mustang?

it is exactly this one?

http://www.doctordiff.com/rear-disc-brake-kit-10.7-rotor.html

Toyota Cressida, I believe 1988 or 1989. The center bore will need to be opened up. I believe that is the mod.

It's a 2003 Mustang Cobra (4.6 4V Supercharged)

And yes, that is the kit