You can see the ledge of plumbers epoxy that I build up under each aluminum channel in order for it to be the right height that would allow the acrylic vents to slide freely without being obstructed by the torso walls.

The pink spill where the programming unit would sit is Bondo auto filler. I tried using this project first, but it was messy and unsatisfactory. Plumbers epoxy is an ideal material. It is just like clay. You can push it into any shape you desire. It can be sanded, drilled, and even tapped.

Since this photograph was taken, the bondo has been sanded away and replaced by a nice ledge of plumbers epoxy.
 
 

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