I've had my 76 since 2006. It's been to the homeland and back. It has served me well, but unfortunately, I've had it parked outside for the past 4 years. It's had an umbrella cover for most of that. Even still, the years have taken their toll and I decided it was time to clean things up a little.

Here's how she looks with the neighbors cat sitting comfortably on the hood.

The floors look great. Especially considering that for the past couple months every rain had resulted in a lake in the interior.

The real question is, what's this plug?

It was tucked away under the foam block in the passenger footwell.

Close up.

Ejection seat connector? Sorry, no idea what it is for.

Smog crap. It went to a speedometer cable junction box (under the foam footpad) It triggered the egr light on the dash. My best answer while buzzed...

Great info. Smog stuff seems the most likely. My 76 is a 49 state car so it must just be part of the harness build and left unused.

After a quick search, it looks like the black/yellow and blue/yellow wires are for California cars with all the emissions stuff and warning lights.

Thanks for the help.

It went to the counter at tripped a dash light at 80000 miles to replace the CAT.

Other end of the plug is in the rear trunk.