10” front drums to K/H on a 71 ??

My 71 demon 340 came with front drums, buddy of mine has a K/H sbp setup with rebuilt calipers, new rotors the spindles, and upper control arms. . I know I’ll need a manual disc/drum master, new wheel bearings, probably a adjustable proportioning valve. Anything else I’m missing? Is this stuff even worth $500? Or should I get a more modern kit? Thanks