66 Dart GT HT Whatsitgonnabe?

Yep manual steering 1 groove pulley. That looks about right. I made my own out of a discarded 2 groove pulley. And cut the power steering groove off.

What diameter is your pulley, Matt? And can you measure from the surface of the table it's lying on up to the center of the groove?

Or is it mounted? In that case, could you measure how deep it is?