I made this horizontal mounting bracket for the BFT warning light. Since my old warning light was mounted close to my outdoor gate lights, I had to offset my new BFT warning light a bit to the right so that it fits.

The model was made in Plasticity. I uploaded both my Plasticity working file (it's a bit messy as I am a beginner) and I also uploaded a STEP file for your convenience. 

You can print this without any supports. I printed it in PETG.

Enjoy!

Also, ignore the poor silicone job on the pics as my silicone was half dry and I did not want to buy a full pack for just a few grams of silicone.