Just got a "new to me" 1970 Monte that had been sitting for 3-4 years and when I got it all the lights except 1 marker light but I had no turn signals or hazards. Drove it a couple of times, maybe 30 miles, now I have no lights what so ever. Car still starts and runs but no headlights, taillights, brakes, dome, nothing. Any ideas where tp start?

 

Check the grounds for rust,check the harness,check the fuses,fuse panel to harness connection.

 

also check all the bulbs and play around with wires(disconnect re-connect wiggle around). Older vehicles tend to have those issues.