I built a Coho and my deck and hull didn't fit together that well at first -- so if you have this problem I'd suggest using as many aids as you need to get it to fit perfectly. You can use bungees, tape, nylon webbing, velco straps -- just about anything you can wrap around the boat to pull the deck ahd hull together. You just glue around these aids, and then go back later and fill in the gaps after you remove the tape, etc.

On Pygmy boats the suggested method: Use strapping tape to hold deck in
> place and a few wires if needed. I used only 2 wires on my Coho but your
> Osprey Double may need more. Unthickened epoxy is used to weld the deck in
> place so the strapping tape can be removed. If you beveled deck and hull
> panels the seam will not need much thickened epoxy to fill the seam.

> Larry C.