While with the family for Thanksgiving today, my father in law wants me to build him an AR w/ a dedicated .22cal upper with a slide fire stock. Ok, no problem, but my concern is how light of a trigger do I need to go with, to get the slide fire stock  to get this to work? Ive heard you need a light trigger to get everything working correctly, as the GI trigger wont work with the slide fire. Also, will a 2 stage trigger, like a SSA-E or even a SSA work, or do I need a light single stage work like in the 4.5-5 lbs single stage work?

HKDUDE got his aluminum AR-22 to work with a1.5 lb Timney trigger, he advised the adjustable trigger is a necessary and he used a short reset.  Check out the pistol and rimfire section here on ARF.COM