The manual shows them using a Quadra engine on it, so the OS GT55 would fit in there even more easily. With the front mounted carb, it would be easier to hook up the throttle and you have it more exposed up front, so you can manually operate the choke as it is easy to get to, so you can flip the choke lever. You may or may not have to make new plywood spacers for the OS engine. I don't know if the wood spacers fit the OS engine or not. But that is not a problem.


The engines are all two stroke, so they all sound about the same though.