A lot to catch up on, finished the interior paint, subflooring is in, the walls have been furred out, wiring has been installed and both skylights are installed. Pictures of all will be coming soon but right now I have some pictures of how I installed the skylights in place of the rescue hatches.
I got the skylights from E Z Tops. http://www.rvskylight.com/rvskylights.htm
The curb of the rescue hatch is 24 5/16" X 24 5/16", OD so I bought the 23" x 23" x 5" high skylight with a 1-1/2" wide flat flange ( 26" x 26" OD ).
Here's the parts for one skylight:
4 31" Gray Composite Deck Balusters
16 Self Drilling Screws Panhead Phillips 10 x 1
10 foot of 1/8" x 1 1/4" aluminum angle
8 2" deck screws
1 tube Urethane sealant/glue ( I used Bostik 1100 Fast Set)
Peel & Seal 6" X 25' Aluminum Roof Repair tape
styrofoam sheet insulation
Here's the composite lumber frame assembled with a little urethane and the deck screws.
Dry fit the frame over the rescue hatch curb to be sure. While you have it in place make a template of the space between the outside of the hatch curb and the inside of the frame corner. Make another of the outside of the hatch curb and the outside of the frame corner.
Use the urethane to glue the skylight to the frame. Miter the aluminum angle to fit over the flange. Use the self drilling screws to attach the angle to the edge os the frame, not through the top so as not to go through the skylight flange.
Use more urethane to seal the angle.
Use the inside corner template to cut the styrofoam to fill the corner spaces and use the outside corner template to cut the roof repair tape. Cut the styrofoam ans tape slightly large so as to get a tight fit on the corners when you put it in place.
Put the styrofoam in place, stick the roof repair tape over it and staple in place. Once the urethane is dry it is ready to install. I'll add picture of the skylight in place and secured soon.