The setting could be taken down to .5mm of free play with fuel pressure running. This is how I do it. Do not prelaod it though as you may have. This will have too much fuel at idle and could allow for fuel to bleed in when sitting. You will have to take apart the housing to get it set back.
WARNING, NEVER take apart the fuel distributor. It will NEVER reseal.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS