Yet besides a missing kick-start (which has provoked some grumbling from fans) and an added fuel gauge (which has elicited no comments), these are unnoticeable.
Once the hundred or more students enrolled in the course discover that the professor never takes attendance, the class shrinks to a less imposing size.
Less prominent secret locations included a nuclear reactor under a University of Chicago football field, the Alabama Ordnance Works for producing heavy water and many others.