Hey I just got a chance to look at this today...I don't see a sqare plug...should it be connected to anything else or should it be open? If so, there is only one open plug anywhere near that in my engine bay. I tried grounding that one as described above and nothing happened with the light. I'm a 22R (carb) if that makes a difference.

 

This is from a 93 V6 but it should look something like this: