Ok, I'll be pulling the cover (s?) off of the fusebox today to get to the diode.
Is the "cover" you mention the black plastic compartment that contains the top layer of fuses? (Is it under those fuses?)
I will report my findings.
1994 C280, dark green metallic
1991 190E 2.6, Black
(sold to another forum member)
2003 Chevy Tahoe LT, Redfire Metallic
1989 Mustang GT Cobra Convertible