<SNIP> ...but if you play with your stock trigger don't file on it or change any angles. Put the hammer springs under the trigger pin and maybe bend then up to reduce tension on the trigger pull. The creep and over travel will be bad but it will lighten it alittle. If you put in screws to adj the engagement and one for over travel it will really help. Engagement in the grip screw and in front of the trigger for overtravel.
Couple of things here.
First, AR trigger group parts are surface hardened ONLY. This means that if you file on them, you take off most/all of the hardened metal and the engagement is now changing rapidly as the softer metal wears. This can cause ADs or worse.
Second, the trigger springs go on top of the trigger pins and ride in the little grooves there. This is what holds the pins in! If you try putting them under the pins, watch the pins so they don't 'walk out' of the lower.
Best thing I've found for stock triggers is a little spring bending and some Tetra Grease. And they still suck. My Service Rifle has a two-stage Jewell, great trigger. Oughta be, for ~ $200 or so. I've shot some RR two-stage, they're not bad but only $50 or so cheaper.
6mmRemington