Usually Shermans used spare track that they could use, but the kit had no spares at all, so I went through my parts box and found a bunch of spares from previous German tanks I've built. The wheels lashed together are a road wheel left over from a Panther G I built a few years ago, and two rear drive wheels from the Sherman kit. Everything is secured to a frame rather than glued straight on. The turret tracks are on a thin frame of scrap photo-etch metal, and the hull stuff is anchored to wood.
The woodwork aspect is new; I used craft/popsicle sticks to create the improv armor on this side, while staves and other smaller bits I made from bamboo toothpicks. The craft sticks I sliced to approprate thickness with a razor saw, then sanded them until they looked right. The toothpicks I sanded down until I'd reached what I wanted; this started as making wood handles for the pioneer tools (I really hate it when these are molded on, so I erased them) and expanded from there.
The little ammo boxes on the, er, 'rear parcel shelf' are made from miliput and first cut, then sanded down to the proper shape. They are supposed to be .30 / .50 cal ammo boxes.
On the front, I built a wooden frame to hold a generous amount of Panther/Tiger tracks in place. there's a bottom board holding the works, held on by PE squares anchoring it to the tank hull. Looking at period pictures, this was one of about a million different ways Sherman crews tried to make their tanks more survivable. This includes everything from sandbags, to actually setting concrete on their tanks, to elaborate trellises filled with sandbags, to scavenged tracks, to actual scavenged armor (IE the front plate of dead tanks, usually Shermans.) My incomplete tracks were 'filled in' with a chopped off bit of a zip tie.
The base is a bit of board I waterproofed, then glopped some celluclay on. It's the first time I've used this paper mache / clay mix, and it is good stuff. I painted it with a dirty mix of black and brown oils. Mud in my experince is really mono-chromatic, so I tried to make it look typical. I then slopped that paint color onto the lower bits of the tank. To get the blotchy thin mud effect over everything, I gave the take two coats of thinly diluted browns/tans, and left little masking compound patches everywhere, which after airbrushing I removed with an old toothbrush. All the layers are protected by future.
The turret was much simpler. The .50 cal MG had to have its really ill-formed handles chopped off, and I never got around to replacing them.
Got a post for the M4/Sherman, but it will have to wait after the current edition of Amerika bombers is done.