Okay, so I've taken the online 609 test so I can purchase R-12. I found some specs online that show the capacity of a 1991 w124 to be 1000 grams, that converts to 38 oz of freon I'm guessing?

I will get it properly evacuated.

So the seals for the expansion port, get those from Mercedes? Do they need to be special for R-12?

Thanks for the reply.