This Work-In-Progress is completed and the mod can be downloaded!
So, done.
We've made custom specs, an animated parking brake, hitch height adjustment, extension options, two working widths, two types of lighting, and decal configurations. The mod will be uploaded to ModHub at the end of June, and we're waiting for its release. I've read several accusations of the model being stolen. I recommend those who have seen it take a look at an old JFAgri spreader and compare its accuracy with mine. Besides the fact that they're the same machines, the model is completely different.
This is what the model looks like in-game. Animations and minor tweaks remain. Still looking for the owner of this spreader.