Like about anyone else with normal bus windows and old sealing, there are leaks at the bottom corners when it rains. Looking at the frame, it's kind of clear that the gap on each lower corner in the window frame is where it's most problematic, as pictured below...
Seems like a pretty easy fix here is to literally weld or otherwise seal off that gap. Then one mostly has to contend with water coming in the sides and top.
Has anyone else done this mod by chance? It seems like this might be a lot better solution than trying to load up the window frame with a ton of sealant. Still will need some, but perhaps not as much?