I think you would lose the self bailing ability and the engine would be so low you would never be able to trim it out of the water when docked, not to mention the lower part of the engine cover would always get over wash.
The only builder I'm aware of that offered a bracket on a boat under 21' was Dusky, and if memory serves... that was on a 20.
Not sure if they still produce that boat or not.
thanks for your comments, maybe i will have a small swim platform made next to the engine, just want something nice for diving that will take an armstrong ladder,,
That extra grab bar on top is key - even with the standard Parker swim ladder setup. I'm surprised its not a standard option, as it makes boarding a lot easier. Very easy add-on project with a high bang-for-the-buck factor.