Idler arm bushings priced at $100 should be roller bearinged.
FirmFeel has these too.

A competent person with a lathe could turn 2 halves out of nylon/delrin and have a similar sturdy design made up.


I converted the stock disbrakes on my own '73 Dart to beefy C-body 11.75" rotors.
Added 'bonus' was the front track width got narrowed by some 3/8 I recall in the process.
Not sure if the same will happen with b-body 11.75 rotors. Would like to know myself as well too.