Connecting object to end of spline to follow as it grows

I'm having trouble connecting an object to the end of a spline (which is under a sweep nurbs). I'm using end growth to grow the spline which is a wire, and can't seem to figure out how to connect the "connecter" bit - let's call it the mesh to the end of the spline/wire. I want it to twist and turn at the same angle as the spline as it grows. Any advice?

I've tried many things in this forum regarding this topic, but can't seem to get it to work from IK handle tag on the spline to XPresso.

Thanks!
Sarah.