Double S - We don't post the process here, because there is some liability. Do a google on 15 minute trigger job and look for a website that is named Sargents Home or something like that. They have a pretty good description that is very similiar to the one we do on GI Stock triggers in the shop.
A couple of words of caution.
1) An AR can double or triple, and even cycle, if you mess with the trigger too far, especially if you are talking going so far as going into ounces.
2) A trigger on a weapon like an AR with a trigger rated in ounces is dangerous and I would personally recommend against it.
3) Order a replacement spring kit for a few bucks from Brownell's before you give this a try, in case you "need" it.

Good luck.
JD