Reply to crookedwrench:
Here is a canopy with homemade sweeps on my D4D. Wire mesh painted black helps with vision for the operator [attachment=65682]CCAAF8C9-CA89-48D8-894F-7F0FCEDDB6E3.jpeg[/attachment] [attachment=65681]F32B9EC9-C3A6-4540-98E1-D4E5033CA251.jpeg[/attachment]

Don't put to much trust in any of the pictured canopies. A true ROPS would be attached to the frame not the fenders. The ROPS must support the whole weight of the tractor plus the impact as bounces down the mountain.
I have 3 canopies built like those pictured, before you start throwing things at me. I did a lot of weed abatement in old walnut orchards. They where to protect my head from limbs, worked very well. I had landowners say things like "I am so glad you have a ROPS, the last guy did not". I would just smile and nod. It was some steep ground by any standards, but crawlers had been working it for years by the time I came along.
The worst was the dirt had been moving down hill for years, so a lot more exposed rocks. Quartering up hill, top track on a rock as big as the D6, bottom track on soft shale. I way faster than saying it bottom track has spun a revulsion or 2 digging a deep whole. All of a sudden I have oil puck out the crankcase breather.
And speaking of sliding on a hillside, don't kid yourself there is no time to jump. I have been 5 to 10 feet down the hill before I knew I was sliding.
If you do build a full on ROPS, don't forget the seat belt. And then you need to have buckled at the time you need it. My neck is way to stiff anymore to watch what is happening behind me to be buckled down on the seat.