With the windscreen trim, clean behind that trim piece and check for rust. Deal with anything you find to properly treat and seal it. Then fill all voids with silicone, push the trim into the silicone and clean any silicone that oozes out.
Leaving a void will allow moisture to accumulate and sit on the metal, leading to rust and by the time you can see it beyond the trim piece you’ll have to cut out the rust to replace it = windscreen out and a LOT of work!
The rust in the rear fender will be from a leak under the rear window trim piece where the other bit of rust is too. Look closely on the tailgate as you most likely have a small rust patch in one lower corner of the rear window. This is another common place where they rust.
Auto doesn’t sound like much fun to me but I realise that manuals aren’t everyone’s cup of tea either.
I hope you get the old girl sorted for the ski season, mine did the two seasons my wife and I did together many years ago now - lifted and EJ’d, the best, it actually climbed hills!
I ran stock wheels with winter tread for the snow months, and took my 27s for off-season 4wd’n in the high country.
Cheers
Bennie