You are so right. I am rebuilding the entire box. Took out every screw, actuator rod, door, bracket, you name it, sanded them down, painted and or clear coated, replaced foam and gaskets, you name it. Then reassembly. I noticed the screw hole for the metal plate where the tubes come out of the box is stripped. So, I went a screw one size large. I saw this was splitting the plenum between the holes, stopped, and epoxied it. Tomorrow I will substitute a small bolt and nut. I hope it's okay to screw that plate in place before working the tubes through. You are so right about the cracking. My big mistake was not coming here first
