Inexpensive to replace, best done when the dash is out. However, I did mine with the dash in, wasn't aware there was a gasket till I saw them on the website here. When I took the originals out they were in tack and not leaking, but wanted for peace of mind. The originals were a fiber/cork looking material and came out in one piece. Note, you will need to remove the wiper arms to install these, if you aren't sure how to do it like I was, just do a quick google. If you have nice paint, take the time to mask off and put a towel down, they might not come off that easy.

1967 Cougar

Green