I'm on 26-10, where the optional taildragger step kit is first mentioned. Is there any need/advantage to purchase the step kit now, or does it simply bolt on afterward (assuming you perform the steps on 26-17)?
You won't need the steps yet. They are relatively easy to fit later.
Even if you don't think you want the steps now I would fit all the optional parts. I can't see how they could be fitted later. I didn't think I needed them (and don't use them) but my wife does, so on they went.