2 seperate problems, 1) headlights 2) cruise control

Im looking at doing some work on the headlight relay on my 1993 infiniti J30. I have the typical problem of the passenger side healight flickering on and off while driving. I was wondering if anyone could give me a detailed process of how to change out the relay, and any other information that would prove to be useful.

The second problem I have encountered is that the cruise control on my car has not worked since i have owened the car (year and a half), When the cruise button is pushed the light turns on but it does not kick in on the car. Any ideas how i might be able to correct this?

Thanks