The Bolt Earth (4x12z is the cheapest item from this partsfiche.
The Interior Light-switch is made up of components including this Controller,illumi which is the most expensive.
Parts such as the Interior Light-switch: Light Assy. *r93l*, Neo Wedge Bulb (a, Sw Assy,rr Def, Light Assy*b-46l* are included in the Civic 1989 (k) 4dr Lx (ka,kl) Interior Light-switch parts fiche.