Part of me wishes I had used thicker Masonite, 1/4″ or even 1/2″, but things turned out pretty well with the 3/16″ and it saved on weight and storage space (I won’t count the cost savings as that would not have been much, especially when seen in the context of the overall cost of the project)

***A SPECIAL THANK YOU to my friend Michael Cudlitz for lending me his pickup — with him at the wheel — and his wood-shop — with him at the table-saw — to make it possible for me to get the 5 pieces of Masonite all cut down to 2’x6′ so they would match up with my foam boards.
THANKS, MIKE!!!