3M 08509
https://www.3m.com/3M/en_US/p/d/b40067023/ Is what was recommended to help seal the windshield gasket to the cab where necessary. Could possibly be that
3M 08578 Strip Caulk -
https://www.3m.com/3M/en_US/p/d/b40068361/ Is what I used to seal the hum to the floor. Not sure where I saw that recommendation. I think I'm also going to use it to seal the bed wheelhouses to the bedsides and floor.
If you are going for patina, I'd either try to find a seam sealer, to fill that gap on the top of the cab, in a semi matching color, either that our you can just seam seal it and try to touch up paint. I'll add, just because it's a patina build, doesn't mean you can't put new paint on some of these problem areas, leaving the 'patina' for the visible outside of the body.