Quite worrying about what to do to it, and take it out and shoot it.
Run it as-is at 1k yards, if that's your goal. See how it does. Come back with results from the 1k yard shooting festiities, and let us know how it - and you - did.
Recommendations will come after that.
Don't mod it until you know what IT can do. If you outshoot it, out of the box, make the mods that you need to get it up to YOUR shooting level.