Disc Brake donor vs Disc Brake kit....

Well, someone offered me quite a bit for the "donor car" so now I am trying to figure out what is the best way to convert to Disc Brakes using a kit? I have read a bit on the scarebird kit, and it seems that if you don't mind crossbreeding manufacturers a bit (which I don't, yes I know, I am not a "purist"), then that kit seems economical, but I am curious as to what all I need to buy to make it work? Is there a comparable kit out there besides scarebird?

Thanks,

John