I've been working over 'Horse-Catcher' before submitting it again.
Here are some perspectives on 'standard manuscript format,' including SFWA members Vonda M. McIntyre and William Shunn.
For one thing, it reminded me to have a cover page.
In the past, I was using three asterisks for scene breaks, and that differs from the norm, which is to use a number sign '#' indented to match paragraph indentation.
One of the things I noticed about Mr. Shunn's format is that he seems to be using the 'define paragraph' function where I normally just use five space-bar hits for indentation. I would never use a half-inch indent as he does, bearing in mind it is a manuscript and not an actual book. His way may be correct.
Going through the book it looked like I would end up with about seventy-five chapters. This is far too many chapters for a book of this length. Tedious as it is, far better to reorganize the material before submission. Twenty-five or thirty chapters is plenty.
There is also one short chapter that is nothing but exposition. Luckily, it's the only one. This chapter might get deleted, or more likely redistributed throughout the story. Even then, much of it is expendable if the same material is covered elsewhere or brought to light by events rather than some invisiable narrator.
Other than that, I've spent four or five days rewriting and editing, and I stand as much chance as the next unknown author of landing the big publishing contract.
With a crowded marketplace and plenty of wannabe authors attending convention after convention, building personal relationships, or attending panels and asking questions, this writer needs whatever edge he can get.