I've discovered that my great great grandfather's unit in the War of the Rebellion now has a more or less official history. The book is called A History of the 27th Wisconsin Volunteer Infantry Regiment in the War of the Rebellion, 1862-1865. It was written in 2001 by Mark H. Knipping, a descendant of a soldier from that regiment. The manuscript is still technically unpublished, although I've learned that it has been part of the State of Wisconsin's Digital Collection now since November, 2006.
Company F, the unit of the regiment in which my great great grandfather served, was one of the first companies recruited in 1862 and they called themselves the Scott Union Rangers. The soldiers in that company came from the townships of Scott, Mitchell and Abbott in Sheboygan County. My great great grandfather enlisted as a replacement troop in October, 1864.
The book is nearly two hundred pages in length. It includes extended quotations from newspaper accounts published during the war of many of the events that took place along with statements issued by the regiment that often provided the basis for news reports.
While the book does contain an enormous amount of carefully documented information, I wasn't able to find any specific information concerning my great great grandfather's death from disease in July, 1865.
Military records also make it clear that Company F was reorganized during the spring of 1864, in between the regiment's two main combat engagements that year. The company's captain was court-martialed in 1864 and his first lieutenant resigned a week later. None of the book's narrative, or its primary or secondary sources, makes any reference that I could find to any incidents resulting in disciplinary action.
Even so, it's a fascinating account, replete with enough verifiable facts so that the regiment's location and activity on almost any given day can be clearly ascertained. I know I'll be spending some time doing just that now that I've received military service records and pension applications from the National Archives for my ancestor and his soldier in-laws.