Disc brake conversion woes

[Nott32]

I picked up a complete front from a 73 c20 for my 1970 c20.

I replaced the brakes and rotors on the donor and the fuel lines so now I am ready to put it on the truck and I am lost.

Will I use the ball joints from my truck now or the ones on the donor suspension? Both the truck and donor have one side riveted in. I plan on replacing both the uppers and lowers when I install but I need to know what year to order on RockAuto.

Thanks!