I'm not trying to screw up anyone's sale here but you may very well be able to fix your headlight.
If it goes all the way up and all the way down (even slowly), I think you're pretty much home free.
I brought mine back from what I thought was dead with the help of guys on this forum and I regret not being able to remember exactly what I did but if you take it apart , inspect it and clean it, it might just be fine. I think I had to solder something in mine but I don't remember. Again, all that stuff was in my post which seems to have vanished. I'm think the title to my post was, "One headlight is making me NUTS" or something like that. Maybe you or someone else can find it ? There was some really good info and pictures in that thread....
My Capri makes the noise under the dash too. It's been doing that for years but the headlights never fail to do their thing. True, I hold my breath every time I hit the headlight switch but ol'faithful rarely lets me down. Such a good car.
Just my 2 cents.
Dave