The following images are of a customer installation of the HKS 700E in a Fisher FP404. These are not posted as endorsement or critique. Rather, an example of what has and can be done. We have reduced image quality to manage file size.
The 404 also presents a fairly straight forward installation. Pictured here, with up Carbs and Ignition components mounted on the engine. (maybe not visible) Alternatively, the carbs can be mounted low and to the rear and the Ignition can be mounted remotely. The fact that a stock exhaust can be used is a big plus in making this installation simple and quiet. If you wish, you can purchase the aluminum base plate with your engine, or you can cut out your own. You are welcome to phone or email to discuss potential propeller and gear ratio concerns.