Yes, you are right. I have just read that link about Oldsmobile 98 Ambulance in Mother, Jugs & Speed and there, in comments, Buc84 and Animatronixx say is a Oldsmobile, built by "Cotner-Bevington", adding Animatronixx, is a 1970 Oldsmobile Cotner/ Bevington Cotington 48" Ambulance.

http://www.imcdb.org/vehicle_109553-Oldsmobile-98-Ambulance-1970.html

No, that's still the 1970 Oldsmobile.
http://www.imcdb.org/vehicle_109553-Oldsmobile-98-Ambulance-1970.html
I'd like to be able to remember where I saw the '62 Pontiac. I know I'm going to have to rent this again to find out.

Come to think of it, all the ambulances you have at that link are Oldsmobiles.

http://www.imcdb.org/movie_74923-Mother,-Jugs-and-Speed.html

I don't know if this ambulance is the 1962 Pontiac Ambulance requested in main page of this movie.
I got from youtube this picture and there says it's a "Cotner-Bevington" ambulance.
I leave you here two links with more information about this type of ambulance
http://www.coachbuilt.com/bui/c/cotner_bevington/cotner_bevington.htm

http://home.comcast.net/~oldsfan/MySite/62cbambulance.html

And now the pic