A lifter is used by many of the class III teams, I assume you're going to race it, so I would say get the lifter, I havn't run that particular boat, so can't say if it would benefit from a bracket as well to set the engine back further. A lifter will gain you top end speed by reducing the drag on the gearbox, but lift it too high and risk losing water pressure and blowing the engine up!
We have found the best lifter of "jack plate" is the Stainless Marine Gorilla 1 which has been superseded by the Gorilla 2 - the new generation one should be fine for your boat.
http://www.stainlessmarine.com/
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