My 71 came with the map light delete plate. My question is if I add the map light will there be an existing plug in the wiring harness to plug it into.

 

Well, first it's not a map light delete. The map lamp package was an extra cost option, not a standard item that could be deleted. Remember these cars came from a time before everything was standard equipment or had to be ordered as Option Package I or however they do it now.

That said, you should find a power lead behind the dash for your map light. Don't have my wiring diagram handy but I think it will be either orange or orange/black stripe. It should be in the area right behind the map light location.

 

I am not sure about 1971, but in 1970, it was the Y60 option.

You got an underhood light, trunk light, map light, and extra underdash lighting as well.

The harness is separate from the main harness.