Kelsey Hayes disc brakes

So when i purchased my brakes they came of another 1969 dart custom
I received the following
Spindles with all hardware
Hubs with all hardware
Discs
Calipers with all hardware

My question is About the part that bolts to the spindle and has the lower ball joint in it that the outer tie rod goes into
I didn't get those when I received my brakes

Can I use the ones from my drum Brakes
Or do i need ones for discs