Kind of a pain in the ass to be honest but I did same to 2 of mine. The receiver steel on the chicoms is thicker by a small amount and they will require some fitting. PG goes on easily. Handguards will likely require a little fitting as well.
Get a dremel and go SLOW.
KVAR has the best stockset selection(get the US stockset screws for it also) and quality for what you are interested in.
You will also need to change out FCG to US manufacture parts to make legal. RSA makes the best by far but you may have to remove a little metal from your selector yoke for the disconnector.
You need a dremel! Makes a good winter weekend project, FWIW, but if you know what to expect(I didn't)it will go easier and hopefully a litlle faster.
If you go with the US FCG you could use a Bulgy buttstock which is 1 1/4" shorter than the US stock. Matter of personal preference.
If you have a foriegn muzzle device then you will need 6 US parts, instead of 5, interchanged.