You always seem to have a handful of the hard to find parts! I already picked up a set of big ball joint arms on here back when I did my swap.
The caliper brackets from a B / R body car to go to the 11.75" rotors using my existing pin on calipers and F body spindles is what I am after like 72blueNblu pointed out. Will have to do a little more research, on what specific cars to target, B/R bodies aren't the easiest to spot for me. Have to hit the local yard and do some browsing, picking out the big boat cars and checking them out on a case by case basis.
Cordoba, New Yorker, Newport, Magnum, Monaco, St Regis, Fury list goes on etc...