Need help on build parts

[Threejs]

I have a greyboe terrain and a proof 6.5 barrel. I need an action and all the bottom metal/mag parts. Since it's a rem 700 footprint I have a lot of options for actions. I'm going to build a 6.5prc. Can I use the wyatts box for that stock? I plan on running factory ammo. Do I need the wyatts box? I want to run a defiance action. How the heck do I know which one? Should I just run a lone peak or something else???