For the shortest pull with the stock trigger and a positive stop (it won't move past the trigger point) adjust it like this (marker on, degassed, with eyes off, makes this a bit easier)-
- Remove frame
- Adjust backwards travel - Back set screws out until trigger sits flush against frame and trigger switch is not depressed
- Adjust trigger switch screw - Turn bottom screw in until trigger clicks - turn it just a little more to be sure that it will always activate
- Adjust forward travel - Turn top screw in until trigger switch is no longer depressed - then just a very little bit more to help reduce bounce and to be sure that the switch will complete a full cycle every time.
You now have the shortest trigger pull available with stock components (haven't tried the flip the switch mod yet). If you want to move the trigger forward to a more natural position you'll have to drill and tap a 3rd set screw for an adjustable back stop position or get an aftermarket trigger with this already done.
To get rid of the side-to-side slop you'll need to shim the trigger within the frame. I did this by carefully grinding a tiny bit off the side of the trigger until I could fit a nylon fiber washer .032" thick (too thick to just drop in) #4 ID x 1/4" OD (available at Home Depot) between the trigger and frame. Proper shims of the correct thickness would be better but I didn't have a supply of these available so I used what I had and carefully made it work.