Fitting a keel & rigg

I am in the process of building a 14' 6' grp clinker style hull, with a 6' beam. The mould has been taken from a very old tub, designed not for sail , but to take an inboard engine. I think it would look stunning if I could build one with a centerboard casing, & put up a gaff rigg. With this statement endeth the knowhow Any advice on how to work this out, or who can work it out for me, would be most welcome, ie : where the drop plate/ centerboard should be positioned, sail area, mast position, etc etc.

We are in middle England so a wee bit landlocked.
Many thanks.

 

The extreme vast majority of powerboat hull forms are very poorly suited to sail conversion. Without pictures of the hull type you're interested in modifying, then further suggestion is pure speculation.

Post some photos so we can have a look see at your project.

 

The best way to balance a daggerboard position and sail plan is to copy those that have sailed and balanced well in the past. Ideally ,one should go for a sail on the one that you plan to base your dropboard and sail plan on. Clinkers who's transom is out of the water can sail well, Dragging a transom will kill sailing performance, but if you are in no hurry, who cares.
Brent