The trick is to put the disc brake spindles on then you can buy the disc brake rotors which are large bolt pattern. The thing with the upper control arm is the disc brake has a bigger hole for a bigger upper ball joint. You can either get the a arm that accepts the bigger ball joint which would be the 73 and later or doctor diff sells a shim that goes over your small ball joint and goes in to that larger disc all for $20. So all in all you really just need to find those spindles and some $20 shims. But I also believe dr. Dif sales, I was reading on here I haven't looked it up for $200 or less. Also remember if you put disc brakes on the front you'll need the new portioning valve that brass piece that's down below your master cylinder usually against the frame. Then of course now you need brake calipers for your disc's. It's a worth while upgrade.
