This should be easy enough (if I had a manual).
Marked with red dot.

Just a single brown wire, single spade connection in it, and it disappears into the firewall.

There's a complete lack of anything on that side to plug it into.

Thanks!

 

It's the power lead for the underhood light. If it's not there on underside of hood above brake booster, look and see if there's any evidence car ever had one, like rough threads on the mounting holes.

Use your test light to check it. It should be hot only when the park or head lights are on. Also check that it's plugged into the fuse block, should be plugged onto a spade terminal on the RH side.

 

That's what I was thinking too about the hood light but I can't seem to locate my wiring diagram right now.

 

Aw jeez, that makes sense, seing as the hood was off when I bought it.

Thanks!

 

Cool, been wondering about that same wire on my car. Glad I didn't chop it off!!! Guess now I need a under hood lite

 

I used mine for a hotwire for my autometer gauge lights, the connector is the same as a lot of others on the car so I made a real clean connection with an extra male plug that I had. Just can not dim the gauges lights but I dont care about that.

 

I think they all had the lead with the underhood light option or not, mine has it and I know it never had one.
I put my new hood pad on and there's a cutout for the light, looks like something's missing, I need an underhood light now.