We are DIN-E spec; I just looked for the spec document (which I'm sure I have, I remember paying for it & downloading it from the ISO website...). Japanese cars can sometimes be different, though. All the head units we have on the shelf here, including Sony, Kenwood, Blaupunkt, Ford and Alpine, require 182mm width holes in the dash.

This fits exactly with the 182mm hole in european (VW, Audi, Mercedes, etc) and many japanese (CRX, Civic, mazda miata, etc) cars. *Some* cars, eg toyotas, can have "captive" dins, where there is a smaller hole, to prevent the stereo from being removed easily.

1989 is fairly old, I know the hondas had the right width but about 3mm extra height in ~1987.

Hugo