Re: marlin model 60
Since the trigger connects to the sear via a trigger bar, were the trigger bar makes contact can have an effect on how hard the trigger is. The adjustment however is made in the stock ie move the trigger guard assy downwards for more leverage on the trigger bar. This is done with shim stock. The only other improvement would be the hammer and sear engagement. The trigger bar springs are already light and would offer no improvement anyway.
Only cowards shoot with their eyes closed....