Additional "trim" rings cut on a bandsaw, and the back plate too. The trim rings give purchase for a perimeter of aluminum sheet (lets the tiny bit of internal heat transfer out easier than a full acrylic box would, and easier to construct). The aluminum gets screwed to the perimeter rings with 4-40 flat head machine screws (drill and tap the plastic).



Gluing a trim ring to one of the upper or lower sheets, in this case uppper (out facing one):



Not to be left out, the reflector and LED parts of the donor are chopped up, rebuilt with a piece of printed circuit board, and so on, to create a new reflective and functional light module (one of 8 to be constructed). Top is original, bottom the new part:



So far:

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