MCr - your chain is 9" wide? Is that chain from a bulldozer? The links in these chains is about 9-10MM from outside link face to the inside link face. Any wider and it would not fit along the case.
Perhaps your thinking top to bottom between the over and under run, essentially sprocket diameter of rear wheel?
Jeez, where did that come from? I slipped and jerked. Thanks for the catch. But its .98" at its full width of a pin. I wasn't thinking anything else, just a goof.
But wouldn't it be the pin top that would be carving into the cases, not the link face? However you measure it. So you'd want to compare at the pin, of a chain that fits and one that doesn't. I haven't really seen one other than pictures (one that has been rubbing) so I assumed the widest point.