The hatch is from a salvaged sailboat I found on EBay for $100. I had to clean it up and replace the 1/2 thick plexiglass which cost another $100. Then I had to build a base from PVC board so I could accommodate the curve of the roof. That took a little bit of creative work but I figured the PVC board would never rot and was pretty easy to shave a curve out of .

I noticed you had a 98 RE with a T444E. Our is a 96 and has "coach" style windows and the DT444E. Our F350 also has the 7.3 PowerStroke (same basic engine with a few differences).
Our solar will be late into the build but I'm looking at FOUR front to rear rails and then mounting panels so that there is is walkway between them for purposes of cleaning, inspection, and snow removal. Want to have that walkway on the rails as well and that way have a complete shade cover over the roof and thus a barrier against solar heating.
You can follow our build at HamSkoolie.com and HamSkoolie (channel) on YouTube.
I am curious about your hatch as that's something I haven't been able to solve other than to buy an expensive boat hatch. Yours looks like a boat hatch but doesn't and I'm wondering what you did?

Hello I was reading about your future solar install and would love to see any information, pictures when you do your solar set up. I have a very similar bus to yours so I'll be following your progress. I also like your signature I have the same thing over my desk at work " We the unwilling led by the unknowing are doing the impossible for the ungrateful, we have done so much for so long with so little we are now qualified to do anything with nothing"