Brother of The Benz, apprentice
With my 1987 W124030 with 176,000 miles, I have the front wheel bearings serviced when the front brake pads are renewed.
I do my front brakes every 40,000 miles.
To properly preload the bearings, as noted, a dial indicator is used to set the free play of the bearing.
With the age of your Benz, why are you replacing the bearings?
It is a rare event for the wheel bearings of a Benz to fail under normal driving.
I would suggest you gain help from a qualified technican, and it isn't a DIY job for the first time anyway.
Happy Trails Beep Beep from The Spiderman in Houston!!!