Weld the upper ball joint in ?

I put a suspension kit in a 67 Valiant and the threads in both the control arms were shot to the point where there were hardly threads anymore. The ball joints threaded in but it was more like they were just cutting their own threads into the control arm. Was forced to tack weld both ball joints in for piece of mind. Figured it'll need another set of A arms anyway if I ever have to do them again.