Use Boiled Linseed Oil, if you are going to use any of the Linseed oils. It has not actually been boiled, but it dries faster.
A tutorial on web sling usage:
http://www.ray-vin.com/frtech.htm
I bought one of the Specials several years ago, because the 1960's rebuild I had been using in Garand matches did not have a lot of tension when I closed the trigger guard. Such is important for an M1 to shoot well. My scores went up a good bit.
Don't be taking the barreled action out of the stock any more than you absolutely have to.