Bolt on Disk brake conversion for 66 Valiant

Many new cars, especially high performance ones, use aluminum hubs. Heck a lot of them use cast aluminum hubs and even cast aluminum control arms. How it holds up is simply a matter of design.

The DoctorDiff 13” cobra style brake kit I run on my Duster has billet aluminum hubs. Aluminum construction is usually stiffer and lighter than steel and cast iron.
My ford work truck has cast alum upper control arms