Stam

Zolatone works well on aluminum and would probably hold up almost as good on the inside of a F/G DB.

The nice thing about gel coat is that it's chemically the same as the rest of the boat and when used in new construction this chemical bond is a great advantage, little or no prep work is needed other than sanding off the unsightly or rough spots. Other types of paint need the surface prepped before applying them. Plus gel coat has a very high viscosity and goes on thick (20 + mils), so it will hide a great deal of sloppy work. This thick film also means it will last a long time and take a great deal of abuse.

The inside of a F/G DB has a good deal of texture from the glass fibers, so prep work can be a little difficult. If the surface can't be sanded easily then I use a stiff wire brush to abrade the surface before applying any type of coating.

It's a very low tech application, roll on the base color and then spray over that with gel coat mixed with webbing solution. Any cheap spray gun will work, quality isn't needed. You just vary the amount of webbing solution to achieve the affect you want, small amounts make it splatter in droplets, more makes long strings.