Look closely at the rail bolt sealing....sometimes there wasn't any sealant put in and the plywood soaks up water........It might be a good idea to open it up and look well ahead of planned roof recoat....
Pac NW and warmer places
1995 E250 EB 5.8 2WD on to a new owner
2006 E350 EB Elect Top 2WD
Hi -- I actually just went to a fiberglass boat and RV repair shop in Denver -- who told me it would probably be cheaper to get a new top than refinish the existing one. He didn't think it was going to leak -- mostly cosmetic at least for 5 or so more years. Not exactly what I was hoping for -- so I'm still trying to see what my options are -- thanks
Another option is the truck bed coating. I did the raptor liner today. Spent a few evenings and half of yesterday removing the rusted roof track hardware. Drilled, cleaned, and filled all of the holes. Sanded the entire top, washed and dried it before spraying. Pretty easy to do. Hoping it will keep the top water tight for another wet Wa winter.