All my utility lights (engine bay trouble light, clove box light and interior light) don't work on my 78' z.  I have a wiring diagram but it does not show the utility lights.  Any ideas on how to fix this?  Thanks!

I suggest you go here and download the 78 280Z wiring diagram in PDF form. I was able to find all of the circuits.

As for how to fix them, download a copy of the 78 FSM. The link to is should be in my signature. Look in the BE section. It has breakouts of the circuits.

Use an ohmmeter, pull the fuses, and verify they are good. Use the ohmmeter to verify the wiring and switches are good. Verify the circuits are grounded in the appropriate locations.