I built a mount for a high-speed rotating beacon (a Federal Signal Firebeam, model FB3MEF - 55 watt halogen lamp) to keep it above my head so it's visible when I'm plowing snow out in the street, especially when it's dark out. Here are several photos so y'all can see how it's done.
This is the overall view from the rear with the light flashing at the camera.
Notice the wire for the rotating beacon is fastened to the right tube and plugs into a connector in the tool box that I added.
The foam pipe insulation pieces on the vertical tubes are there to keep the seat from rubbing on the tubes when I lean back.
The vertical tubes are made from 1/2" EMT ("thinwall" electrical conduit). The tubes are connected to solid plugs at top and bottom by pins through holes in the tubes and the plugs. The plugs are welded to 3/4" angle stock. The lower angle is bolted to factory-made slots at the rear of the tractor. I used heat-shrink tubing to remove slop where the tubes go through the plastic fittings at the rear of the X500.
The upper angle bar is connected to the tubes in the same way as the bottom, but it has a plate welded on for the light to mount to (with a magnet) and I used small cotter pins for a semi-permanent connection.
This view is with the tubes disconnected and lifted to just above their mounted position so you can see the solid plugs which they connect to.
I added a new "cigarette lighter" socket in the rear of the tool box so that I didn't have to trip over the wire when plugging it in below the steering wheel. I also filed a notch into the edge of the tool box so that the wire has a place to go while the door is fully shut.
Now all I need is some snow to plow!