I have a few more things to add to the Marlin Model 60 trigger modifications mix (I have a brand new 60SN, sold the scope on the bay for $20 so it was $169!)
1) I found the serrations on the trigger to be bothersome after several hundred rounds so I filed them off and polished with very light sandpaper, very comfortable now. Took 5 minutes, the trigger metal is very soft.
2) You will in time figure out the position of the trigger assembly in relation to the action will affect the amount of play in the system and there is fore/aft play in the fit of the trigger guard assembly in the stock. Marlin tells you to move the action/receiver/barrel assembly as far back as possible (though mine is pretty much held firm when placed in the stock) and the trigger guard assembly as far forward as possible as this brings the two assemblies as close together as possible, which is a good idea. This means the tolerances between all the levers and such will be at their minimum and any movement between the action and trigger assembly will only increase the distances between parts which, while adding play, won't be unsafe. However if one doesn't tighten the screws properly (or they just loosen up on their own accord) it might be possible for the trigger guard assembly to move rearward, changing the trigger action. I put a thickness of cardboard between the rearmost part of the trigger guard and the stock to take up this thickness and ensure the trigger guard won't move. Make it thick enough to be a moderate interference fit.
3) If you don't want to go to all the trouble to install the two setscrews (or one setscrew and JB Weld the trigger) to reduce the play at the two ends of the trigger movement try putting a piece of tubing in the trigger hole that the limiter pin goes through (the larger hole in the triggger, the smaller of the two pins). This will reduce (but not eliminate) the play to get to the actual trigger/hammer/sear movement as well as the movement after hammer release. You can get the tubing at any competent hobby shop or hardware store, usually brass or aluminum.