- I had my pivot and forward facing axis not set up right in Blender before export.
So the arm and claw was actually rotating correctly but it didn’t produce the desired result.
(I had it set up in a certain way because I was going to combine animation with it but I was testing without animation … long story) - The tutorial that I watched with the Rinterp node must have been outdated because I simply deleted that node and now it works fine.
Its actually extremely simple. This is all you need:
It works on Z, X and Y.
It also works as is if you do an attachactortoactor with the claw and arm attaching to the little robot body on event begin play. No need to invert the transform. Its right on just as is. I guess that is because the find look at rotation node and set actor rotation overrides the “keep world” setting in the attachactortoactor node…
Here is video of the desired result 
