Charlie,
the body styles are how these forums are broken up: take a look at the page before this & you'll see you're asking primarily about 124's: the '86-95 E-class.
As for the wiring harness, MB had some poor quality wiring harnesses that went into most of the car line for a few years; do a search & you'll find the exact years, all in the early '90s. Roughly $1200 repair jobs with labor.
the body styles are how these forums are broken up: take a look at the page before this & you'll see you're asking primarily about 124's: the '86-95 E-class.
As for the wiring harness, MB had some poor quality wiring harnesses that went into most of the car line for a few years; do a search & you'll find the exact years, all in the early '90s. Roughly $1200 repair jobs with labor.