It's on my winter project list for some year, but who knows If I will ever get to it. We have lots of compost and we get manure when we can for addinto the garden, like 20 yards at a time, so it sure would be helpful. When I started welding I ended up working in ready mix plants and gold mines. We had everything from brand new to over a hundered years old (seriously, it was from before the First World War and riveted) I have worked on several different screen plants over the years, and built a few. For a screen, the woven wire screens can be had in any size you want, expanded steel does not last long at all. try a woven wire with around a 3/4 opening,
The ones with three sides and a screen over the top work well, Put a tongue on one end and some old axle on the other. Your oversized will fall off the back and you will have screened materials in the bin underneath.
The best design I saw (and hope to copy) had a shaft underneath the screen with two disks side by side (they each were on a tapered hub), each disk had a large hole. By clocking the holes from 180* apart to 0* apart the shaking could be adjusted to the materials, then the high side of the screen could be radjusted until the material remained on the screen until it was worked. Then a set of springs used on the adjusters allowed the operator to tap it with the bucket to clean the screen.
You can always just build a grizzly, steel on old Chevy coil springs