Well, as far as I know, 1982 was the only year that all Mercedes had a 85MPH speedometer- or at least the 300SDs. Starting again in 1983, the 300SD's had a 140? MPH speedo. The 85MPH would confirm it is a 82, but I never heard of a 82 500SEL North American model. But since it is in MPH, I assume it is a NA model, unless someone changed the cluster in it.
1993 Mercedes 400SEL 4dr
2012 Honda Civic LX 4dr
1972 Chevrolet Caprice Kingswood Estate 9-passenger wagon
1973 Pontiac Grand Ville 4-dr hardtop sedan
1988 Mercedes 300SEL (was mine, now mothers)