Hey there, thanks for the reply's.

I think we are going to make do with the forward only as my grandad neither wishes to purchase another ECS nor tell the person (my aunt) that bought him it as a gift that it doesnt suit the purpose) My grandad has built this more as a project of something to do with his time i would think and he said to me all he wants now is to get it floating, i don't think he is all to worried about the practicality of it for boating purposes and he won't be competing or anything of that sort with it.

About the water cooling, do i put the input pipe behind rudder on the back? so water is flowing away from the opening to the pipe? then where do i put the output? I don't know what a "transom" is, sorry. Thanks again everyone.