Bombard Typhoon 305
Somewhere or other I've seen questions like this before, and I was interested in doing the same.
From what I recall of the answers, the general thinking was to sell the SIB and buy a RIB.
I bet it would be difficult to get the design and fitting right, and the materials wouldn't be cheap either. Then there's the time factor..........
Sorry to be a grump, but I do really think you'd be better off getting a nice little RIB where all the work's been done for you.