I was thinking about your foam walls for your walk through, you might be wasting your time with my grommet idea. I think it will take too much time and still might not look very good. My new idea is to use vinyl "j-channel". This is the stuff they use for putting up siding around windows. You could attach strips to the sides of your walls (you already have the bottom taken care of with the 2x4.) , then feed the foam through the top. It would hold like a piece of glass in a picture frame. I think it would give a cleaner look and would be an easier way to remove the foam.
It's just an idea so if you don't like it, no harm done. I am also not sure how tight the channel would be against the foam. You may have to research that.
Just another thought, you could run the channel horizontally in lieu of vertical to save money and avoid the seam between panels.
Thank you for the beautiful Halloween card. The artwork is spectacular and we enjoyed the enclosed poem. I hope the raging storm is not hitting too close to home. Happy Haunting - Debby aka Madame Turlock
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