Summer2Go - I am trying to do the same thing you are. When we had a PUP we used the pool noodle as a lightweight rain gutter, and it worked well. It was surprisingly stable. The picture below is from Pinterest, not from my camper. What I've been trying to find the time to do is anchor the space blanket to the noodle. I'm going to try the easiest idea first, and that is to attach the blanket to the noodle with binder clips. I will attach them on the noodle first and then put the noodle under the roof in the same manner as we always have. The binder clips will go on the side toward the inside of the camper so that the noodle will hold down the space blanket.
Shouldn't be a problem, right?
It's been 18 years since I chased a 3 year old after working a full time job. I just haven't had the energy to work on the project yet. Let me know if you understand and how you work out your idea.