Found this posted on CS by Keeper. Basically he did a roster analysis for every FCS team to try and quantify the impact of players lost using the 2013 stats. This may not be completely accurate as he had to rely on whatever online materials he could find (and whether or not they were up to date) but it's very impressive nonetheless.
http://home.comcast.net/~keepersfootball/fcsspringconf.htm
http://home.comcast.net/~keepersfootball/fcsspringconf.htm
