Help: looking for person who picked me up hitchhiking

This is a very long shot. In summer 1987 I was hitchhiking across the US
following the dead and was picked up by a German on his last leg of a world tour. He drove me almost 2000 miles to alpine valley Wisconsin. I gave him an extra ticket and a cup of mushroom tea when we got there. I believe his name was Karl and - not surprisingly- he was a Mercedes Benz mechanic,

Anyway. Thanks for reading