Just for illustration, I glued this bottom deck sheeting using weight (I normally use a vacuum bag system). Once the glue is applied to the skin, slide the assembly together from the front, creating a bit of wedge action. With the edges of the skin sticking up on the sides, you will have to block up the weights. I also added some tape in a few places to help apply a bit of pressure from the sides.

In the end the result is satisfactory and the edges of the skin can be sanded flush to the core.

In one of the pics, you will see that the skin cracked and overlapped slightly at the tail end of the core. This is not a big deal, as we will be sanding the bottom radius area away later to install the lower part of the vertical fin.