The trick I use and I don't know if this is what you are looking for, but I go to a site like partsamerica.com. Go to the replacement parts for your '63 and look up something like lower ball joint. Then open another window at partsamerica and enter a 1968 coronet and check the same part, which I did. Looks like they share the same part numbers for balljoints and bushings, so I'd guess you're looking for a b-body setup. The only thing I don't know is if the big parts, like control arms are the same. But if the ball joints are the same, you would only need the spindle and the rest of the brake parts for a b-body to convert to disks. Which means just about any brake system from the bigger cars will work, even 73 and up a-body's. Is this what you are looking for? Double check me on the part numbers to be sure.
