Really? I have used the self leveling Dicon and it works better for me. Make sure you don't use silicone with acetic acid anywhere wiring as it will corrode the electrical connections.
If it's a fiberglass roof, you have many options. Rubber roof it must be Dicor or an equivalent.
Silicone, or better yet Proseal Caulking/Sealant. We used Proseal for all non runner roof applications with great success. It's a bit pricey, but not near as expensive as having to replace roof substrate due to water damage.
Silicone is made to cure and stick on non-porous surfaces, like fiberglass. What do you use on the sides around windows and trim? Pro Seal is silicone based....
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Steve and Vicki
2 kids
2011 Dodge 3500 CTD Outdoorsman
(Tweaked!!)
2013 Columbus 320RS-ITS HERE!!