My 1982 2.6 liter automatic almost certainly does not have such a relay. It is night how. There is no such relay shown on the electrical schematic. As I recall, from reading the factory manuals for later years, at the library ( those surviving after a !@#$%!&*^! tore a nice color-coded one out ), relays for the headlights appeared first in 1984. Maybe 1983.

I have been free of light problems for several months now. My last handslap on the fuse box must have been a masterstroke.