Ironman Canopy + roof cage/rack

[Stuart77]

Has anyone retro-fitted a roof cage or flat rack onto canopy rail mounts? I'm looking at getting just a flat rack and really don't want it over the cabin, rather have it over the canopy. I have a '15 MN with an Ironman canopy and as far as I can see I can put 100kg on top of it. I considered U-bolting a cage straight to the rails but figure it might be easier, stronger and safer to take the rails off and get some brackets made to fit straight into the existing mount holes.
Anyone done anything similar?

Cheers