Welcome aboard TJmedic,
Personally I would freak out with an etec 90 on a 16' FiberCraft. Here's a link to fellow forum member Joey's sweet FiberCraft which was powered by a 30 hp Nissan... I don't know your boat but I doubt it was designed to hang 335 lbs off the transom, especially in the skinny waters you speak of.
http://www.classicseacraft.com/joeyf...aft/index.html 