I just finished building my .204 Ruger and am starting to think about what i need to build a 7mm WSM. I'm thinking i need a new mag, follower, barrel, bolt head and barrel. Am i missing anything. I'm also planning to send in my action to SSS for a time and true job after i go on my prairie dog shoot this spring. One question i have is if i get a whole bolt assembly from midway in the magnum head can i send that also and have it trued or does it only work with on bolt per action? Here is my rifle specs as of right now. Is there anything I'm missing in doing this change over?

Savage model 12 stainless action
Light weight accutrigger
NSS recoil lug
26" Shlien stainless steel select match grade barrel in .204 ruger
B/C Medalist tactical stock
EGW 1 piece scope base