Here's how it works.
The lights that I found (on ePay) have a stud mount. I made a piece out of a short section of tubing and a 10mm nut and had it welded to the guards. The housings that I cut from the EMT slide over the stud mounts to conceal the mount and the wiring. As I said in the last post, the slots in both parts keep the housings lined up.
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When the light is screwed in tight, it holds the housing in place. The back side is cut shorter and at the same angle of the seat stays so that it will butt into the frame.
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The housings will be painted the same as the guards. Also, the bottom edge of the left guard will be trimmed to match the right.
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