The Mk1 interior lamp fitted on the trim panel between the headliner and side windows takes a different bulb than the later cars. Some early Mk2s were fitted with this same lamp. Got a Mk2 and not sure which lamp you have? If your interior lamp assembly and hand grab are separate units, you have the late interior lamp. If the two units (lamp & hand grab) are combined into one assembly then you have the early style interior lamp. This bulb is also used in some of the aftermarket lamps fitted to the center console interior lamp in the wood dash cars.