For whatever it is worth, the window sticker on my 1987 300E also lists the headlight wipers and washers as standard equipment (it's getting a little hard to read after all these years in the glove box!)

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John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E