Few tech questions after a tune-up

[MyFirstBenz]

Hey everyone...I was working on my '75 W115 200 today and had a few questions. I figured why not ask around! My car hasn't been running great, so I adjusted the distributor cap on the stem and it came back to life. I've learned that's the shadetree way to adjust timing. I think it got off when some friends were adjusting the point gap. Anyways...

1. I had a problem with it about a month ago. I was coming off the highway, and it died as I stopped to pay a toll. It started up again, but then died soon after. I found out in the tinkering around that my alternator was dead and had been for a few weeks. It is now fixed. Could this have caused the stall at the toll gate as well? I seem to remember reading somewhere that engine dying when decelerating can be an alternator symptom. I'm just hoping I don't have another problem and the alternator, which is now fixed, was the issue.

2. I learned about blowby and the PCV. I did the "teakettle" test and it the cap does a little rocking and rolling, but nothing major. I adjusted the valve clearances to help that out. One other thing I found out though, is that my car runs better with the blowby just blowing into the air rather than back into the manifold and carb. Other than the environmental issue, is it bad to run that PCV line into the air rather than back in to be reburned? Keep in mind I live in a third-world country where most of the cars blow black smoke in copious quantities as they roll down the roads.

3. What is the fan in the very front of the car in front of the radiator? AC blower fan? What does it mean if the AC is not on and it runs? It happened to me when I was working on the engine. Just a fluke?

4. I live in a country that rains half the year, and I have a car that is 35 years old. Ergo, there are some rusty spots. What are some techniques to halt the progress of rust? I know the best is to pull the panels and have them redone, but I'm thinking cheaper. I was going to try epoxy paint and fiberglass to seal water out of the bad spots. The rust is mainly just body issues (especially the trunk). Any other suggestions? I've seen the rust stopper products you can get in the US, and I may pick some of those up when I'm there if that's the best idea.

Thanks for any help!