you looking for nitro or gas or fe? nitro contact andy green on here he can steer ya to nitro or gas probably fe club is in bradonton at tom Bennett park now
try a mcdonalds straw with radio box tape try it in different places under the boat see where it works best then u can put a more perminate dam in the right place
this sounds like a really bad idear with a hydro....don't know what type of fish u would be after but hook a decent large mouth bass and you wont see that hydro again soon