I have a 1968 15' starcraft fiberglass boat with a 55hp Johnson. I use the boat for fishing a lot and want to buy an electric trolling motor for as cheap as possible. How well would a 30Lbs thrust motor due? Could it move the boat against light wind or waves? I just want to be able to move very short distances while fishing without having to constantly start and stop the main engine, or as a plain B in case the old Johnson was to quit while on the lake.