interchangeability
 

Can anyone tell me what year and model cars have interchangeable parts for my 1989 420sel,or know of a web site that will give me this info?ALL OTHER YEAR AND MODELS WILL BE VERY HELPFULL.

Thats is a tough question as some parts will interchange off all 126 chassis cars. Some will exchange on 116 motors. Some parts will be found on all MB models of that year and some will be found on different models and different years. There will be parts that won't interchange between your 89 420SEL and other 89 model 420SELs. It just isn't that simple.

I am looking for a pass. side electric mirror from other years and models.

That'll be quite a list. I'll take a stab at US version cars:

81-85 300SD
86-87 300SDL
90-91 350SD/L
81-85 380SE/L
88-91 300SE/L
86-91 420SEL
84-85 500SEL
86-91 560SEL

There are also non US variants such as:

80-? 280S/E/L
85-? 260SE
other years and wheelbase lengths of models in the US list.

Basically any mirror for a W126 will work. You probably want to keep the remote adjustment function. If you want heated mirrors you'll have to stick to the 500 and 560, I think. I don't know if you can use a heated mirror if you don't have the connections for it.

I don't know if the finish is different between years and models. I don't know if all are convex (objects in the mirror... ).

Sixto
91 300SE
87 300SDL
81 300SD

Any power mirror from any 126 chassis will work, and probably any W124 chassis as well.

THANKS! I can now look for a used one.

The US W124 right side mirror is not the mirror image of the left, if that matters to you.

I didn't get into the W126 coupes since I don't know if those mirrors will fit a sedan.

Sixto
91 300SE
87 300SDL
81 300SD