All the window holes are cut, its a lot of work. I dulled out the nibbler so I rotated the bit 180 degrees.
The rearward windows are in the galley, that’s why they are higher.
The little access flap on the driver side under the window will be a downdraft vent for the range, and maybe external gas/electrical/whatever access for the appliances.
Eventually I’ll replace the driver window with a less drafty rv version as well, but I want to get the current windows done first.
I went back on my decision to use threaded fasteners and instead I’ll be riveting.
When attaching different metals, I think you need to be careful of galvanic reaction. I will try and mitigate it by sealing the aluminum frame to the bus body with butyl tape, and making sure the steel on the bus is well coated in paint.
For the rivets, I selected a stainless fastener, which I will coat each one with PTFE goop (see pics below). This will eventually, maybe, cause the window frame to act as the sacrificial anode, in like 10-20 years. (Long enough for me!)