There is an inner plastic cone in the skylight above the shower. It is held on to the ceiling with white screws, probably about 6 or 8 total, which use a square drive screwdriver. Have a vacuum ready, as some foam debris, insects, etc., will fall into the shower and bathroom. Be careful with the inner skylight cone; it is very thin, delicate, and brittle molded plastic. A replacement unit runs $48 to $140 depending on where you buy it.
You should be able to remove the inner skylight unit, remove the reflective insulation, and replace. You may want to, as I have done, put the reflective insulation cut to fit just around the exterior of the white plastic cone where it is not visable. Affix with strong duct tape so it won't bounce up into your view when you hit bumps in the road.
Do not break the seal or remove the outer skylight. However, double check the dicor lap sealant to make sure there are no cracks developing, and if necessary clean and apply more dicor self-leveling lap sealant.
The upper skylight is supposed to be clear, but gets cloudy with age and sunshine. It can be brought back to new condition on the exterior with an electric drill with a soft buffer (or headlight-kit polisher) and Meguiar's Plastic-X clear plastic cleaner/polish. Regular treatment with the Plastic-X and a micro-fiber towel should keep it clear and new looking.
Good look with your project.
2014 F150 SCrew 4x4 Max Tow Heavy Duty Payload 3.5 Ecoboost 6.5' bed Ingot Metallic Silver
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