In terms of hours, I'm not sure how many. I guess it all depends on how experienced you are and how many hours you are able to spend in a row. I for one had not done any major work on a car ever 9for christsakes I don't even change my own oil!), but with the knowledge that it could be done with enough time and effort I figured I would just learn as I worked.
When I was doing work on my car, we had a reasonaly warm Minnesota winter, but I also had a full-time job and classes to take care of as well. All told, I put the thing on blocks September 20, 2001 and was able to drive it in late April of this year. Project car indeed! I guess if you have something else you can drive while you are working and a decent place to do the work, then time is not that much of a concern necessarily
Not sure about the neutral revving question...hope this helps.