The 48" deck on the 520-8 I've been working on is a spare I had in the barn.
The Horses deck when I purchased it "was the pits." I'm reworking that deck little by little.
Hardware, wheel axles, blades, and patching some rotted areas. Here's a peek-a-boo at work in progress. Patch is bolted, new SS bolts w/ locking nuts. Then I'll MIG the patch to the original deck. A through cleanup and (I just happen to have a gallon of IH red that'll do for now) a paint job. Of course a new drive belt.
I have the belt guards that'll be sanded / sand blasted and painted too.