Does anyone know where you can find some nice, detailed, pictures of the drive units on this grader?

My dad is working on one right now. Broke one of the main drive chains. Those chains are heavy, you have very little area to work, and the adjustments appear to be impossible.

He hasn't gotten the chain on yet, but he checked the other side and that chain is hitting the bottom of the case so it needs to be tightened.

I haven't seen it all yet, but he said it seems like the adjustment is damn near impossible with that setup but he has a very poor picture to go off from.

Does anyone know anything about these graders?