How do I point a limb towards another part?

Stuff with welds, especially Motor6Ds are not my strong suit and I am completely lost from what I am seeing online. I’ve made a custom rig that is composed of 4 parts: torso, head, right arm, left arm. All of them have a motor6d with the part0 as the torso. I want the left arm and the right arm to both point to different parts and I know I have to do something with the motor6d but I’ve seen tons of things online and I’m confused on the right way of doing this. Any help is much appreciated