The 51, 3100, 3 window I purchased had rust holes above the driver side windshield. It was pretty nasty. Instead of trying to patch it I decided to replace the roof and also decided to make it a 5 window while I was at it. Bought the roof panel, inner support panels above the windshield, inner and outer rear window panels from one of the friendly vendors in KC. It was a lot of work but it wasn’t rocket surgery. Just take some good measurement before you start and brace her up a bit before you start. Definitely doable, especially if you’re just going to do the rear window panels.
Dan
35 CC Case 38 Chevy Pickup 51 3100 AD 58 3100 Apache Fleetside