sash

Hi guys, first post. After searching a bit, I've figured out that the door tape that comes on the pillars of the sedan isn't just vinyl wrap. Here's my question: Has anyone here replaced their door tape? Any advice? Mine is in rough shape, and I'd like to get it looking nicer if possible...

I am looking to replace the left rear door window sash, the small one between the main window and the stationary quarter window, due to heavy rust. Dealership is looking to charge me $300 hundred. I believe I am calling it right, the L RR Quarter Window Sash, but all the diagrams I am finding...