I came across this interesting article on the first production Mustang on AutoWeek.com written by Roger Hart.  The article asks the question is the Mustang pictured above which sits in the Henry Ford Museum in Dearborn, Michigan really the first production Mustang or was Ford not even suppose to sell it in the first place.  Some will say without a doubt its the first production Mustang because of it's 100001 VIN but Randy Paddock of ClassicMusclecars.com says not so fast.  The article goes on to tell the side of Randy Paddock and why he thinks he has the first Mustang that was suppose to be sold to the public.  It's definately worth the time reading as it contains alot of history.  Check it out here