Three-pin or four-pin?

[strelnik]

I have to replace the turn signal relay/flasher relay on my 83 240D.

Pelican parts recommends two versions from Porsche sources but no info on how/why they are different:

000-821-10-63-M252 which is a four-pin

and

000-821-10-63-A-INT which is a three-pin relay

Since the Pelican info doesn't tell me how to distinguish one from the other, I'd like to know if anyone can tell me where this relay is located.

I'll pull it over lunch and order one from somebody.

Thanks