What does "co imposition" mean? What is a "step out"? Never heard that terminology on a boat before.
If you are talking about a bolt-on teak swim platform, its probably not strong enough for anything larger than 5 HP. If you are talking about a molded-in platform that is part of the hull, with the right bracket it could hold a much bigger engine.
Regardless, a 25 HP motor on your boast would be overkill.
I have had a "kicker" on every boat I've owned since 1968. Show us some pics of your application and I can respond with pics showing a potential solution.
