Hi
I have a couple of old Mercedes Busses/Vans around that year.
Could you fill in your profile and maybe post a couple of photos of the vehicle to know what we're dealing with here.
Then I can answer some of your questions.
Lots of times DMV or owners get the year wrong or even the model and then it's anybody's guess what is really helpful info.
It's helpful to know where the person is that I am 'talking' to.
Thanks
Alex