Has a College Football game ever ended 66-8?
Exactly once. On September 17, 2005, Texas A&M beat SMU 66-8, and no College Football game before or since has ended that way. When it happened it was a scorigami, the first 66-8 in league history.
That makes 66-8 the 1819th most common final score out of 2,215 that have ever occurred in College Football. One point away, 67-8 has happened 1 times and 66-9 has happened 1 times.