RV Repair: Leak in Overhead Cabin in Fourwinds 1992 29, silicon caulk, fiberglass sheet

Question
Hello Ron! One of the mostly used questions. How do I seal overhead cabin properly? The water is coming in probably from both front corners . The corners are no more properly sealed outwardly and do not cover the skin of the RV. They no more overlap. Now I have the wooden flat that is over the fiberglass pulled out, because it had become soft and humid. also the left and right wooden-flat / wall disguising.
With which materials do I stick the wooden flat again on the fiberglass and which kind of wood (Veneers or unveneered) you suggest? Where are suitable materials available? Please tell me the name of the adhesive materials and the sealing masses. Can one touch with resin and use as an adhesive between woodenflat and fiberglass sheet? In expectation of an answer  

Answer
Most motorhomes are constructed of a "sandwich type" panel:
the outer panel is glued to styrofoam on one side and wooden paneling on the other.  All are placed in a jig and pressed together.  Pretty simple construction.  Special glues are used to keep from melting the styrofoam.
You would best be served by contacting a local company that does such repairs to get an estimate what it would take to fix and if they would sell you the materials to do it yourself.
Most RV stores sell a variety of caulks and sealants but whatever you do, don't use silicon caulk on a motor home, it just makes a mess.