Re: 300 WM Sendero SF 11 Questions
The jewell comes with pretty simple instructions. Should be ok if your mechanically inclined.
The mag mod is easy if your handy with a dremell.
Take a look at wyatts. Theyre pretty reasonable. If you have some extra coin, HS or Badger.
I have the SF II in 7 mag, and the rifle is heavy enough that I think you will be fine without a break, even in 300 win.