Below is the water heater shroud screwed back in place. I used 3/4" RV clay tape between the trailer body and shroud, as the shroud does not lay completely flush against the trailer, so the clay tape fills the void. Later this year when I pull out the front and rear window frames to re-caulk them, I will also use the clay tape. Water does not penetrate it, and it will be easier to finish caulk the seam between window frame and trailer. The clay tape that I took off the shroud from 1964 was still pliable. The floor around the water heater is in really good shape, so the clay tape stood up all those years against the elements, with near zero water leaks.
Below is the new Kitchen Vent cover installed. In comparison I am holding the old brittle, broken and faded original cover. The new vent cover is a little longer, but it still fits in, and I think it looks great. I copied all the original screw holes except the bottom two, accounting for the length difference of the new cover. This vent cover came from Vintage Trailer Supply.