Refer to the manual
In the 107 Chassis manual (complete description of the work) it says to pull the pitman arm off the output shaft of the steering gearbox. Attach a divice to the steering wheel and measure the torque. There is a maximum torque value not to exceed. This is torque of the steering box, not connected to the wheels (or anything). THe value is something like 110 N/mm.
The output shaft is on a tapered gear and the adjustment snugs the gears deeper into the tapered teeth. If it is too tight it binds and wears the bearing surfaces in the gearbox case. Better a little too loose than too tight.
Regarding steering play, after adjustment there may be a low torque value in the middle of the range and that is acceptable for a steering gear not adjusted for a long time.
1985 Mercedes 500SL Euro (Gray market)
1995 BMW 520i Euro (Gray market)
1992 BMW 525it Wagon
1994 Honda Del Sol Si