I found a William McCrady who served in Capt. William Key's Ohio Volunteers in the war of 1812.Those volunteers were supposed to have come from Ross County, Ohio.That might be a help to you.Ross County is two counties from what is now West Virginia and two counties from Kentucky and there is one county between Ross County, Ohio and Perry County, Ohio.
My William was born in either New York or Vermont (depends on the census that you read) between 1815 and 1820 (again, depends on census.)My William was also not a very prosporus man and he did not have a great attachment to the "E" in the name.
His father was supposed to have been born in Scotland.I have found that there seems to be a lot of McCready activity in Western Pennsylvania in the late 1700's and early 1800's and there is a large branch of the family in West Virginia.
There was an old family legend about 5 brothers who came to this country and each went different ways, but you know how "creative" family legends can be.
If your James was born in Vermont in the late 1700's he could be a cousin or brother of my William.I just don't know enough about my William to trust making that leap.
These McCready/McCrady/McCreedy folks can be somewhat difficult to track.Makes you wonder if they were running from the law.