No wonder you're having trouble finding 48 vent window rubber: 48 didn't have vent windows. If your truck has vent windows, the doors are not original 48. More likely your doors are 51-54. So yes, the 51 vent rubbers will work on your "48."

For the metal strips for the sidewall cards, check MNSmith's build thread. He fabricated some.

https://www.stovebolt.com/ubbthread...suburban-update-mnsmith.html#Post1280468


1951 Chevy Panel Truck